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Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
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1

Imaging and sensing based on muon tomography  

SciTech Connect

Techniques, apparatus and systems for detecting particles such as muons for imaging applications. Subtraction techniques are described to enhance the processing of the muon tomography data.

Morris, Christopher L; Saunders, Alexander; Sossong, Michael James; Schultz, Larry Joe; Green, J. Andrew; Borozdin, Konstantin N; Hengartner, Nicolas W; Smith, Richard A; Colthart, James M; Klugh, David C; Scoggins, Gary E; Vineyard, David C

2012-10-16T23:59:59.000Z

2

Improving scintillation crystals using muon tomography  

SciTech Connect

The cosmic ray muon scanning array provides information on NaI(T1) crystals using some 65,536 trajectories, each measuring the NaI(T1) response to high energy muons. With this information, it is possible to use established computer-aided-tomography techniques to deconvolute these integrated responses and produce a detailed picture of the detector's interior.

Dowell, D.H.; Fineman, B.J.; Sandorfi, A.M.

1987-01-01T23:59:59.000Z

3

Imaging and sensing based on muon tomography - Energy Innovation ...  

Subtraction techniques are described to enhance the processing of the muon tomography data. Skip to Content. ... Hydropower, Wave and Tidal; Industrial Technologies ...

4

Discussion - Next Step for Fukushima Daiichi Muon Tomography  

Science Conference Proceedings (OSTI)

Specification of Fukushima Daiichi Muon Tomography (FMT): (1) 18-feet (5.5-m) drift tube, 2-inch (5-cm) diameter; (2) 108 tubes per layer; (3) Unit layer = 2 layer (detection efficiency: 0.96 x 0.96 = 92%); (4) 12 or 16 layer per module; (5) 16 layers allows momentum analysis at 30% level; (6) 2 module per super module (5.5 x 11 m{sup 2}); and (7) FMT = 2 super module. By deploying MMT next to a research reactor, we will be able to measure the impact of low level radiation fields on muon tomography and reconstruction processes. Radiation level during reactor operation is {approx}50 {micro}Sv/h which provides similar radiation environment of inside the FMT radiation shield at Fukushima Daiichi. We will implement coincidence algorithm on the FPGA board.

Miyadera, Haruo [Los Alamos National Laboratory

2012-08-13T23:59:59.000Z

5

Our Next Two Steps for Fukushima Daiichi Muon Tomography  

SciTech Connect

After the vast disasters caused by the great earthquake and tsunami in eastern Japan, we proposed applying our Muon Tomography (MT) technique to help and improve the emergency situation at Fukushima Daiichi using cosmic-ray muons. A reactor-tomography team was formed at LANL which was supported by the Laboratory as a response to a request by the former Japanese Prime Minister, Naoto Kan. Our goal is to help the Japanese people and support remediation of the reactors. At LANL, we have carried out a proof-of-principle technical demonstration and simulation studies that established the feasibility of MT to image a reactor core. This proposal covers the next two critical steps for Fukushima Daiichi Muon Imaging: (1) undertake case study mock-up experiments of Fukushima Daiichi, and (2) system optimization. We requested funding to the US and Japanese government to assess damage of reactors at Fukushima Daiichi. The two steps will bring our project to the 'ready-to-go' level.

Miyadera, Haruo [Los Alamos National Laboratory

2012-04-11T23:59:59.000Z

6

Detection and Imaging of High-Z Materials with a Muon Tomography Station Using GEM Detectors  

E-Print Network (OSTI)

Muon tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons is a promising technique for detecting and imaging heavily shielded high-Z nuclear materials such as enriched uranium. This technique could complement standard radiation detection portals currently deployed at international borders and ports, which are not very sensitive to heavily shielded nuclear materials. We image small targets in 3D using $2\\times 2 \\times 2$ mm^3 voxels with a minimal muon tomography station prototype that tracks muons with Gas Electron Multiplier (GEM) detectors read out in 2D with x-y microstrips of 400 micron pitch. With preliminary electronics, the GEM detectors achieve a spatial resolution of 130 microns in both dimensions. With the next GEM-based prototype station we plan to probe an active volume of ~27 liters. We present first results on reading out all 1536 microstrips of a $30 \\times 30$ cm^2 GEM detector for the next muon tomography prototype with final frontend electronics and DAQ...

Gnanvo, K; Bittner, W; Costa, F; Grasso, L; Hohlmann, M; Locke, J B; Martoiu, S; Muller, H; Staib, M; Tarazona, A; Toledo, J

2010-01-01T23:59:59.000Z

7

Nuclear Waste Imaging and Spent Fuel Verification by Muon Tomography  

E-Print Network (OSTI)

This paper explores the use of cosmic ray muons to image the contents of shielded containers and detect high-Z special nuclear materials inside them. Cosmic ray muons are a naturally occurring form of radiation, are highly penetrating and exhibit large scattering angles on high Z materials. Specifically, we investigated how radiographic and tomographic techniques can be effective for non-invasive nuclear waste characterization and for nuclear material accountancy of spent fuel inside dry storage containers. We show that the tracking of individual muons, as they enter and exit a structure, can potentially improve the accuracy and availability of data on nuclear waste and the contents of Dry Storage Containers (DSC) used for spent fuel storage at CANDU plants. This could be achieved in near real time, with the potential for unattended and remotely monitored operations. We show that the expected sensitivity, in the case of the DSC, exceeds the IAEA detection target for nuclear material accountancy.

Jonkmans, G; Jewett, C; Thompson, M

2012-01-01T23:59:59.000Z

8

Imaging of high-Z material for nuclear contraband detection with a minimal prototype of a Muon Tomography station based on GEM detectors  

E-Print Network (OSTI)

Muon Tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons in matter is a promising technique for detecting heavily shielded high-Z radioactive materials (U, Pu) in cargo or vehicles. The technique uses the deflection of cosmic ray muons in matter to perform tomographic imaging of high-Z material inside a probed volume. A Muon Tomography Station (MTS) requires position-sensitive detectors with high spatial resolution for optimal tracking of incoming and outgoing cosmic ray muons. Micro Pattern Gaseous Detector (MPGD) technologies such as Gas Electron Multiplier (GEM) detectors are excellent candidates for this application. We have built and operated a minimal MTS prototype based on 30cm \\times 30cm GEM detectors for probing targets with various Z values inside the MTS volume. We report the first successful detection and imaging of medium-Z and high-Z targets of small volumes (~0.03 liters) using GEM-based Muon Tomography.

Gnanvo, Kondo; Hohlmann, Marcus; Locke, Judson B; Quintero, Amilkar S; Mitra, Debasis

2010-01-01T23:59:59.000Z

9

Performance of a Drift Chamber Candidate for a Cosmic Muon Tomography System  

SciTech Connect

In the last decade, many groups around the world have been exploring different ways to probe transport containers which may contain illicit Special Nuclear Materials such as uranium. The muon tomography technique has been proposed as a cost effective system with an acceptable accuracy. A group of Canadian institutions (see above), funded by Defence Research and Development Canada, is testing different technologies to track the cosmic muons. One candidate is the single wire Drift Chamber. With the capability of a 2D impact position measurement, two detectors will be placed above and two below the object to be probed. In order to achieve a good 3D image quality of the cargo content, a good angular resolution is required. The simulation showed that 1mrad was required implying the spatial resolution of the trackers must be in the range of 1 to 2 mm for 1 m separation. A tracking system using three prototypes has been built and tested. The spatial resolution obtained is 1.7 mm perpendicular to the wire and 3 mm along the wire.

Anghel, V.; Jewett, C.; Jonkmans, G.; Thompson, M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Armitage, J.; Botte, J.; Boudjemline, K.; Erlandson, A.; Oakham, G. [Ottawa-Carleton Institute for Physics, Department of Physics, Carleton University, Ottawa, Ontario (Canada); Bueno, J.; Bryman, D.; Liu, Z. [Advanced Applied Physics Solutions, Vancouver, British Columbia (Canada); Charles, E.; Gallant, G. [Canada Border Services Agency, Ottawa, Ontario (Canada); Cousins, T.; Noel, S. [International Safety Research, Ottawa, Ontario (Canada); Drouin, P.-L.; Waller, D. [Defence Research and Development Canada, Ottawa, Ontario (Canada); Stocki, T. J. [Health Canada, Ottawa, Ontario (Canada)

2011-12-13T23:59:59.000Z

10

GEANT4 Simulation of a Cosmic Ray Muon Tomography System with Micro-Pattern Gas Detectors for the Detection of High-Z Materials  

E-Print Network (OSTI)

Muon Tomography (MT) based on the measurement of multiple scattering of atmospheric cosmic ray muons traversing shipping containers is a promising candidate for identifying threatening high-Z materials. Since position-sensitive detectors with high spatial resolution should be particularly suited for tracking muons in an MT application, we propose to use compact micro-pattern gas detectors, such as Gas Electron Multipliers (GEMs), for muon tomography. We present a detailed GEANT4 simulation of a GEM-based MT station for various scenarios of threat material detection. Cosmic ray muon tracks crossing the material are reconstructed with a Point-Of-Closest-Approach algorithm to form 3D tomographic images of the target material. We investigate acceptance, Z-discrimination capability, effects of placement of high-Z material and shielding materials inside the cargo, and detector resolution effects for such a MT station.

Hohlmann, Marcus; Gnanvo, Kondo; Helsby, Jennifer; Pena, David; Hoch, Richard; Mitra, Debasis

2008-01-01T23:59:59.000Z

11

Performance Expectations for a Tomography System Using Cosmic Ray Muons and Micro Pattern Gas Detectors for the Detection of Nuclear Contraband  

E-Print Network (OSTI)

We present results from a detailed GEANT4 simulation of a proposed Muon Tomography System that employs compact Micro Pattern Gas Detectors with high spatial resolution. A basic Point-Of-Closest-Approach algorithm is applied to reconstructed muon tracks for forming 3D tomographic images of interrogated targets. Criteria for discriminating materials by Z and discrimination power achieved by the technique for simple scenarios are discussed for different integration times. The simulation shows that Muon Tomography can clearly distinguish high-Z material from low-Z and medium-Z material. We have studied various systematic effects that affect the performance of the MT and the discrimination power. The implications of the simulation results for the planned development of a prototype MT station are discussed.

Gnanvo, Kondo; Helsby, Jennifer; Hoch, Richie; Mitra, Debasis; Hohlmann, Marcus

2008-01-01T23:59:59.000Z

12

Design and Construction of a First Prototype Muon Tomography System with GEM Detectors for the Detection of Nuclear Contraband  

E-Print Network (OSTI)

Current radiation portal monitors at sea ports and international borders that employ standard radiation detection techniques are not very sensitive to nuclear contraband that is well shielded to absorb emanating radiation. Muon Tomography (MT) based on the measurement of multiple scattering of atmospheric cosmic ray muons traversing cargo or vehicles that contain high-Z material is a promising passive interrogation technique for solving this problem. We report on the design and construction of compact Micro-Pattern Gas Detectors for a small prototype MT station. This station will employ 10 tracking stations based on 30cm x 30cm low-mass triple-GEM detectors with 2D readout. Due to the excellent spatial resolution of GEMs it is sufficient to use a gap of only a few cm between tracking stations. Together with the compact size of the GEM detectors this allows the GEM MT station to be an order of magnitude more compact than MT stations using traditional drift tubes. We present details of the production and assemb...

Hohlmann, M; Grasso, L; Locke, J B; Quintero, A; Mitra, D

2009-01-01T23:59:59.000Z

13

GEANT4 Simulation of a Scintillating-Fibre Tracker for the Cosmic-ray Muon Tomography of Legacy Nuclear Waste Containers  

E-Print Network (OSTI)

Cosmic-ray muons are highly penetrative charged particles that are observed at sea level with a flux of approximately one per square centimetre per minute. They interact with matter primarily through Coulomb scattering, which is exploited in the field of muon tomography to image shielded objects in a wide range of applications. In this paper, simulation studies are presented that assess the feasibility of a scintillating-fibre tracker system for use in the identification and characterisation of nuclear materials stored within industrial legacy waste containers. A system consisting of a pair of tracking modules above and a pair below the volume to be assayed is simulated within the GEANT4 framework using a range of potential fibre pitches and module separations. Each module comprises two orthogonal planes of fibres that allow the reconstruction of the initial and Coulomb-scattered muon trajectories. A likelihood-based image reconstruction algorithm has been developed that allows the container content to be determined with respect to the atomic number Z of the scattering material. Images reconstructed from this simulation are presented for a range of anticipated scenarios that highlight the expected image resolution and the potential of this system for the identification of high-Z materials within a shielded, concrete-filled container. First results from a constructed prototype system are presented in comparison with those from a detailed simulation. Excellent agreement between experimental data and simulation is observed showing clear discrimination between the different materials assayed throughout.

Anthony Clarkson; David J. Hamilton; Matthias Hoek; David G. Ireland; Russell Johnstone; Ralf Kaiser; Tibor Keri; Scott Lumsden; David F. Mahon; Bryan McKinnon; Morgan Murray; Sian Nutbeam-Tuffs; Craig Shearer; Cassie Staines; Guangliang Yang; Colin Zimmerman

2013-09-13T23:59:59.000Z

14

Range tomography: combining the practicality of boolean tomography with the resolution of analog tomography  

Science Conference Proceedings (OSTI)

The objective of early network tomography approaches was to produce a point estimate for the performance of each network link (Analog tomography). When it became clear that the previous approach is error-prone in practice, research shifted to Boolean ... Keywords: Network tomography, localization, performance metric

Sajjad Zarifzadeh; Madhwaraj Gowdagere; Constantine Dovrolis

2012-11-01T23:59:59.000Z

15

Computed Tomography Status  

DOE R&D Accomplishments (OSTI)

Computed tomography (CT) is a relatively new radiographic technique which has become widely used in the medical field, where it is better known as computerized axial tomographic (CAT) scanning. This technique is also being adopted by the industrial radiographic community, although the greater range of densities, variation in samples sizes, plus possible requirement for finer resolution make it difficult to duplicate the excellent results that the medical scanners have achieved.

Hansche, B. D.

1983-00-00T23:59:59.000Z

16

Computed tomography status  

SciTech Connect

Computed tomography (CT) is a relatively new radiographic technique which has become widely used in the medical field, where it is better known as computerized axial tomographic (CAT) scanning. This technique is also being adopted by the industrial radiographic community, although the greater range of densities, variation in samples sizes, plus possible requirement for finer resolution make it difficult to duplicate the excellent results that the medical scanners have achieved.

Hansche, B.D.

1983-01-01T23:59:59.000Z

17

Experimental Adaptive Bayesian Tomography  

E-Print Network (OSTI)

We report an experimental realization of an adaptive quantum state tomography protocol. Our method takes advantage of a Bayesian approach to statistical inference and is naturally tailored for adaptive strategies. For pure states we observe close to 1/N scaling of infidelity with overall number of registered events, while best non-adaptive protocols allow for $1/\\sqrt{N}$ scaling only. Experiments are performed for polarization qubits, but the approach is readily adapted to any dimension.

Konstantin Kravtsov; Stanislav Straupe; Igor Radchenko; Neil Houlsby; Sergey Kulik

2013-03-07T23:59:59.000Z

18

Positron Emission Tomography (PET)  

DOE R&D Accomplishments (OSTI)

Positron emission tomography (PET) assesses biochemical processes in the living subject, producing images of function rather than form. Using PET, physicians are able to obtain not the anatomical information provided by other medical imaging techniques, but pictures of physiological activity. In metaphoric terms, traditional imaging methods supply a map of the body's roadways, its, anatomy; PET shows the traffic along those paths, its biochemistry. This document discusses the principles of PET, the radiopharmaceuticals in PET, PET research, clinical applications of PET, the cost of PET, training of individuals for PET, the role of the United States Department of Energy in PET, and the futures of PET.

Welch, M. J.

1990-01-00T23:59:59.000Z

19

Proton computed tomography  

SciTech Connect

The use of protons or other heavy charged particles instead of x rays in computed tomography (CT) is explored. The results of an experimental implementation of proton CT are presented. High quality CT reconstructions are obtained at an average dose reduction factor compared with an EMI 5005 x-ray scanner of 10:1 for a 30-cm-diameter phantom and 3.5:1 for a 20-cm diameter. The spatial resolution is limited by multiple Coulomb scattering to about 3.7 mm FWHM. Further studies are planned in which proton and x-ray images of fresh human specimens will be compared. Design considerations indicate that a clinically useful proton CT scanner is eminently feasible.

Hanson, K.M.

1978-01-01T23:59:59.000Z

20

Resistivity Tomography | Open Energy Information  

Open Energy Info (EERE)

Resistivity Tomography Resistivity Tomography Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Resistivity Tomography Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Downhole Techniques Exploration Sub Group: Well Log Techniques Parent Exploration Technique: Resistivity Log Information Provided by Technique Lithology: Stratigraphic/Structural: Hydrological: Thermal: Cost Information Low-End Estimate (USD): 60.986,098 centUSD 0.061 kUSD 6.098e-5 MUSD 6.098e-8 TUSD / foot Median Estimate (USD): 76.227,622 centUSD 0.0762 kUSD 7.622e-5 MUSD 7.622e-8 TUSD / foot High-End Estimate (USD): 106.7110,671 centUSD 0.107 kUSD 1.0671e-4 MUSD 1.0671e-7 TUSD / foot Time Required Low-End Estimate: 1 days0.00274 years

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

The 1981 ocean tomography experiment: Preliminary results  

Science Conference Proceedings (OSTI)

Preliminary results from a 1981 test ocean acoustic tomography experiment are presented. The system deployed in the southern North Atlantic

The Ocean Tomography Group; R. C. Spindel

1982-01-01T23:59:59.000Z

22

Earthquake Forecast via Neutrino Tomography  

E-Print Network (OSTI)

We discuss the possibility of forecasting earthquakes by means of (anti)neutrino tomography. Antineutrinos emitted from reactors are used as a probe. As the antineutrinos traverse through a region prone to earthquakes, observable variations in the matter effect on the antineutrino oscillation would provide a tomography of the vicinity of the region. In this preliminary work, we adopt a simplified model for the geometrical profile and matter density in a fault zone. We calculate the survival probability of electron antineutrinos for cases without and with an anomalous accumulation of electrons which can be considered as a clear signal of the coming earthquake, at the geological region with a fault zone, and find that the variation may reach as much as 3% for $\\bar \

Bin Wang; Ya-Zheng Chen; Xue-Qian Li

2010-01-17T23:59:59.000Z

23

Atom Probe Tomography and Transmission Electron Microscopy ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Atom probe tomography (APT) and analytical transmission .... of a Leaking Type 316 Socket Weld in a Boron Injection Tank Sampling Line.

24

Crosswell Seismic Tomography | Open Energy Information  

Open Energy Info (EERE)

2013 DOI Not Provided Check for DOI availability: http:crossref.org Online Internet link for Crosswell Seismic Tomography Citation Schlumberger. Crosswell Seismic...

25

Prospects for Atomic-Scale Tomography  

Science Conference Proceedings (OSTI)

Abstract Scope, Atomic-scale tomography (AST) may be defined as any technique that ... Initial Age Hardening and Nanostructural Evolution in a Cu-Ni-P Alloy.

26

Radiation interactions for tomography. Revision 1  

SciTech Connect

There are new requirements emerging in the field of tomography: the need for spatial resolution in the micrometre range, atomic species specificity, and quantitative density discrimination.

Zolnay, A.S.

1985-05-20T23:59:59.000Z

27

NEUTRON IMAGING, RADIOGRAPHY AND TOMOGRAPHY.  

SciTech Connect

Neutrons are an invaluable probe in a wide range of scientific, medical and commercial endeavors. Many of these applications require the recording of an image of the neutron signal, either in one-dimension or in two-dimensions. We summarize the reactions of neutrons with the most important elements that are used for their detection. A description is then given of the major techniques used in neutron imaging, with emphasis on the detection media and position readout principle. Important characteristics such as position resolution, linearity, counting rate capability and sensitivity to gamma-background are discussed. Finally, the application of a subset of these instruments in radiology and tomography is described.

SMITH,G.C.

2002-03-01T23:59:59.000Z

28

Application of Computed Tomography to Microgravity Combustion  

Science Conference Proceedings (OSTI)

This paper describes applications of computed tomography (CT) to combustion phenomena under microgravity conditions. Infrared Thermography (IT) has been considered as a promising method for two-dimensional measurement of flames. We have applied IT to ... Keywords: computed tomography, diffusion flame, infrared thermography, microgravity combustion, spectroscopy

H. Sato; K. Itoh; M. Shimizu; S. Hayashi; Y. Fujimori; K. Maeno

1999-12-01T23:59:59.000Z

29

Simultaneous CT and SPECT tomography using CZT detectors - Energy ...  

A method for simultaneous transmission x-ray computed tomography (CT) and single photon emission tomography (SPECT) comprises the steps of: injecting a subject with a ...

30

Axial Tomography from Digitized Real Time Radiography  

DOE R&D Accomplishments (OSTI)

Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.

1985-01-18T23:59:59.000Z

31

Axial tomography from digitized real time radiography  

SciTech Connect

Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

Zolnay, A.S.; McDonald, W.M.; Doupont, P.A.; McKinney, R.L.; Lee, M.M.

1985-01-18T23:59:59.000Z

32

Buried Interface Analysis Using Atom Probe Tomography  

Science Conference Proceedings (OSTI)

Contributions of Atom Probe Tomography to the Understanding of Steels · Control of p-n ... Relationships in a Series of Co-Cr-Cu-Fe-Ni-Al High Entropy Alloys.

33

Atom Probe Tomography for Industrial Applications - Programmaster ...  

Science Conference Proceedings (OSTI)

Contributions of Atom Probe Tomography to the Understanding of Steels · Control of p-n ... Relationships in a Series of Co-Cr-Cu-Fe-Ni-Al High Entropy Alloys.

34

Mathematical Problems of Thermoacoustic Tomography  

E-Print Network (OSTI)

Thermoacoustic tomography (TAT) is a newly emerging modality in biomedical imaging. It combines the good contrast of electromagnetic and good resolution of ultrasound imaging. The mathematical model of TAT is the observability problem for the wave equation: one observes the data on a hyper-surface and reconstructs the initial perturbation. In this dissertation, we consider several mathematical problems of TAT. The first problem is the inversion formulas. We provide a family of closed form inversion formulas to reconstruct the initial perturbation from the observed data. The second problem is the range description. We present the range description of the spherical mean Radon transform, which is an important transform in TAT. The next problem is the stability analysis for TAT. We prove that the reconstruction of the initial perturbation from observed data is not H¨older stable if some observability condition is violated. The last problem is the speed determination. The question is whether the observed data uniquely determines the ultrasound speed and initial perturbation. We provide some initial results on this issue. They include the unique determination of the unknown constant speed, a weak local uniqueness, a characterization of the non-uniqueness, and a characterization of the kernel of the linearized operator.

Nguyen, Linh V.

2010-08-01T23:59:59.000Z

35

Positron Emission Tomography (PET) and Positron Scanning  

Office of Scientific and Technical Information (OSTI)

DOE R&D Accomplishments DOE R&D Accomplishments Search All Database Web Pages for Go The Basics Home About What's New FAQ Contact Us Laureates Nobel Laureates Fermi Laureates Nobel Physicists Nobel Chemists Medicine Nobels Explore Insights SC Stories Snapshots R&D Nuggets Database Search Browse Reports Database Help Finding Aids Site Map A - Z Index Menu Synopsis Blog Archive QR Code RSS Archive Tag Cloud Videos Widget XML Bookmark and Share Positron Emission Tomography (PET) and Positron Scanning Resources with Additional Information Positron Emission Tomography (PET) Scanner Courtesy Lawrence Berkeley National Laboratory 'Positron Emission Tomography ... [is a medical imaging technique that] can track chemical reactions in living tissues and merges chemistry with biological imaging. Its strength has been in studies of the brain where there has been significant progress in investigations of drug addiction, aging, mental illness, and neurogenic disorders. Positron Emission Tomography (PET) had its genesis in hot-atom chemical research supported by the Chemical Sciences Division of the Office of Basic Energy Sciences. Through this research it was learned, over many years, how to prepare short-lived positron emitters such as 18F whose half-life is 110 minutes. In 1975, the molecule [18F]fluorodeoxyglucose was successfully synthesized at Brookhaven National Laboratory (BNL) and set the stage for Positron Emission Tomography of the human brain.'

36

TE Connectivity Finds Answers in Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

TE Connectivity Finds Answers in TE Connectivity Finds Answers in Tomography TE Connectivity Finds Answers in Tomography Print Thursday, 22 August 2013 10:50 TE Connectivity is a world leader in connectivity-the $13 billion global company designs and manufactures more than 500,000 different electronic connectivity products for the automotive, energy, industrial, broadband communications, consumer device, healthcare, aerospace, and defense industries. TE Connectivity has a long-standing commitment to innovation and engineering excellence. Their products help address challenges arising from companies' need for energy efficiency, always-on communications, and ever-increasing productivity. Recently, a team led by TE's senior manager of materials development, Dr. Jerzy Gazda (at left), has been investigating how ALS tomography capabilities can help the company develop more efficient connectors.

37

Evaluation of Turbine Blades Using Computed Tomography  

E-Print Network (OSTI)

Turbine blades are high value castings having complex internal geometry. Computed Tomography has been employed on Turbine blades for finding out defects and internal details. The wall thickness, rib thickness and radius of curvature are measured from the CT slices. The discontinuities including blockages of cooling passages in the cast material can be detected. 3D visualization of the turbine blade provides in extracting its internal features including inaccessible areas nondestructively, which is not possible through conventional NDE methods. The salient features for evaluation of turbine blades using Tomography are brought out.

C. Muralidhar; S. N. Lukose; M. P. Subramanian

2006-01-01T23:59:59.000Z

38

Positron Computed Tomography: Current State, Clinical Results and Future Trends  

DOE R&D Accomplishments (OSTI)

An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

1980-09-00T23:59:59.000Z

39

Parallel implementation of stochastic inversion of seismic tomography data  

Science Conference Proceedings (OSTI)

In this paper parallel implementation of stochastic inversion of seismic tomography data was presented. Classical approach to travel time tomography assumes straight line of seismic rays between sources and receives points and isotropy of geological ... Keywords: inverse problem, master-slave paradigm, seismic anisotropy, seismic tomography

Maciej Dwornik; Anna Pi?ta

2011-09-01T23:59:59.000Z

40

Wireless Tomography, Part I: A Novel Approach to Remote Sensing  

E-Print Network (OSTI)

Wireless Tomography, Part I: A Novel Approach to Remote Sensing R. C. Qiu, M. C. Wicks, L. Li, Z. Browning.12@us.af.mil Abstract--Wireless tomography, a novel approach to remote sensing, is proposed--radio frequency tomography, remote sensing, cognitive radar, cognitive radio. I. INTRODUCTION The ever increasing

Qiu, Robert Caiming

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Advanced Instrumentation for Positron Emission Tomography [PET  

DOE R&D Accomplishments (OSTI)

This paper summarizes the physical processes and medical science goals that underlay modern instrumentation design for Positron Emission Tomography. The paper discusses design factors such as detector material, crystalphototube coupling, shielding geometry, sampling motion, electronics design, time-of-flight, and the interrelationships with quantitative accuracy, spatial resolution, temporal resolution, maximum data rates, and cost.

Derenzo, S. E.; Budinger, T. F.

1985-04-00T23:59:59.000Z

42

Three-dimensional fluorescence lifetime tomography  

Science Conference Proceedings (OSTI)

Near-infrared fluorescence tomography using molecularly targeted lifetime-sensitive, fluorescent contrast agents have applications for early-stage cancer diagnostics. Yet, although the measurement of fluorescent lifetime imaging microscopy (FLIM) is extensively used in microscopy and spectroscopy applications, demonstration of fluorescence lifetime tomography for medical imaging is limited to two-dimensional studies. Herein, the feasibility of three-dimensional fluorescence-lifetime tomography on clinically relevant phantom volumes is established, using (i) a gain-modulated intensified charge coupled device (CCD) and modulated laser diode imaging system, (ii) two fluorescent contrast agents, e.g., Indocyanine green and 3-3'-Diethylthiatricarbocyanine iodide differing in their fluorescence lifetime by 0.62 ns, and (iii) a two stage approximate extended Kalman filter reconstruction algorithm. Fluorescence measurements of phase and amplitude were acquired on the phantom surface under different target to background fluorescence absorption (70:1, 100:1) and fluorescence lifetime (1:1, 2.1:1) contrasts at target depths of 1.4-2 cm. The Bayesian tomography algorithm was employed to obtain three-dimensional images of lifetime and absorption owing to the fluorophores.

Godavarty, Anuradha; Sevick-Muraca, Eva M.; Eppstein, Margaret J. [327 Votey Building, Department of Computer Science, University of Vermont, Burlington, Vermont 05405 (United States); 1011 Richardson Building, Photon Migration Laboratories, Texas A and M University, College Station, Texas 77843 (United States); 327 Votey Building, Department of Computer Science, University of Vermont, Burlington, Vermont 05405 (United States)

2005-04-01T23:59:59.000Z

43

Industrial tomography applied to reactor safety  

SciTech Connect

Work has begun which explores the use of Computed Axial Tomography (CAT), boundary detection, and internal surface reconstruction techniques in industrial nondestructive testing applications. This initial work is intended to inform the reader of the existence and interrelated nature of these techniques through the use of a realistic simulation of an industrial inspection problem.

Kruger, R.P.

1977-01-01T23:59:59.000Z

44

Ground-based Microwave Cloud Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Microwave Cloud Tomography Microwave Cloud Tomography Experiment, SGP, May 15-June 15, 2009 Lead Scientist Dong Huang, BNL Co-Investigators Al Gasiewski, UC Boulder Maria Cadeddu, ANL Warren Wiscombe, BNL Radiation Processes Working Group March 30, 2009 multiple radiometers All good cloud radiation modelers should close their airplane window shades so as not to be corrupted by the spectacle of real 3D clouds. - Roger Davies In case you forget to do this, you see 3/30/2009 ARM RPWG 2 Effects of cloud structure on radiation 3/30/2009 ARM RPWG 3 Typical climate model - Cloud fraction & mean water content - Horizontally uniform clouds, no side radiation - Assumption on overlap Courtesy of Bernhard Mayer Cloud structure important to radiation - Cumulus (Benner & Evans 2001, Pincus et al. 2005), deep convection (DiGiuseppe &

45

Photon-number tomography and fidelity  

E-Print Network (OSTI)

The scheme of photon-number tomography is discussed in the framework of star-product quantization. The connection of dual quantization scheme and observables is reviewed. The quantizer and dequantizer operators and kernels of star product of tomograms in photon-number tomography scheme and its dual one are presented in explicit form. The fidelity and state purity are discussed in photon{number tomographic scheme, and the expressions for fidelity and purity are obtained in the form of integral of the product of two photon-number tomograms with integral kernel which is presented in explicit form. The properties of quantumness are discussed in terms of inequalities on state photon{number tomograms.

O. V. Man'ko

2012-12-23T23:59:59.000Z

46

A wavelet phase filter for emission tomography  

Science Conference Proceedings (OSTI)

The presence of a high level of noise is a characteristic in some tomographic imaging techniques such as positron emission tomography (PET). Wavelet methods can smooth out noise while preserving significant features of images. Mallat et al. proposed a wavelet based denoising scheme exploiting wavelet modulus maxima, but the scheme is sensitive to noise. In this study, the authors explore the properties of wavelet phase, with a focus on reconstruction of emission tomography images. Specifically, they show that the wavelet phase of regular Poisson noise under a Haar-type wavelet transform converges in distribution to a random variable uniformly distributed on [0, 2{pi}). They then propose three wavelet-phase-based denoising schemes which exploit this property: edge tracking, local phase variance thresholding, and scale phase variation thresholding. Some numerical results are also presented. The numerical experiments indicate that wavelet phase techniques show promise for wavelet based denoising methods.

Olsen, E.T.; Lin, B. [Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Mathematics

1995-07-01T23:59:59.000Z

47

Field implementation of geophysical diffraction tomography  

SciTech Connect

Geophysical diffraction tomography is a new technique that shows promise as a tool for quantitative subsurface (below-ground) imaging. The approach being used is based upon the filtered backpropagation algorithm, which is a mathematical extension of the reconstruction software used in conventional X-ray CAT scanners. The difference between this method and existing methods is that the new algorithm rigorously accounts for diffraction effects through an exact inversion of the wave equation. This refinement is necessary in that it admits the use of acoustic and long-wavelength electromagnetic waves, allowing tomography to be taken from the laboratory to the field. ORNL's effort in geophysical diffraction tomography involves reducing the filtered backpropagation algorithm to practice. This requires the design and construction of field instrumentation as well as the development of an improved algorithm. The original algorithm requires the imaged region to be illuminated by plane waves. This requirement simplifies the algorithm but complicates its field implementation in that plane waves are difficult to generate. Consequently, ORNL has been working to generalize the filtered backpropagation algorithm to allow a broader range of incoming wave fields which can more easily be realized in the field. The instrumentation aspects involve the selection of appropriate sonic sources and receivers along with the development of a state-of-art, portable, computer-controlled, multichannel data acquisition system. 5 references, 6 figures.

Witten, A.J.; Stevens, S.S.

1984-01-01T23:59:59.000Z

48

Recent Advances in Atom Probe Tomography for Microstructural ...  

Science Conference Proceedings (OSTI)

In-situ Ultra Fast Micro-tomography for Material Characterization · In situ Characterization of Surfaces and Buried Interfaces Using Total Reflection Inelastic ...

49

The Application of Atom Probe Tomography to Oxide-Dispersion ...  

Science Conference Proceedings (OSTI)

Contributions of Atom Probe Tomography to the Understanding of Steels ... Investigation of the Microstructure-Property-Processing Relationships in a Series of ...

50

Time-dependent seismic tomography and its application to the...  

Open Energy Info (EERE)

changes in Earth structure are commonly determined using local earthquake tomography computer programs that invert multiple seismic-wave arrival time data sets separately and...

51

Minimally invasive diagnostic imaging using high resolution Optical Coherence Tomography  

E-Print Network (OSTI)

Advances in medical imaging have given researchers unprecedented capabilities to visualize, characterize and understand biological systems. Optical Coherence Tomography (OCT) is a high speed, high resolution imaging technique ...

Herz, Paul Richard, 1972-

2004-01-01T23:59:59.000Z

52

THE THERMAL SUNYAEV-ZEL'DOVICH TOMOGRAPHY  

Science Conference Proceedings (OSTI)

The thermal Sunyaev-Zel'dovich (tSZ) effect directly measures the thermal pressure of free electrons integrated along the line of sight and thus contains valuable information on the thermal history of the universe. However, the redshift information is entangled in the projection along the line of sight. This projection effect severely degrades the power of the tSZ effect to reconstruct the thermal history. We investigate the tSZ tomography technique to recover this otherwise lost redshift information by cross-correlating the tSZ effect with galaxies of known redshifts, or alternatively with matter distribution reconstructed from weak-lensing tomography. We investigate in detail the three-dimensional distribution of the gas thermal pressure and its relation with the matter distribution, through our adiabatic hydrodynamic simulation and the one with additional gastrophysics including radiative cooling, star formation, and supernova feedback. (1) We find a strong correlation between the gas pressure and matter distribution, with a typical cross-correlation coefficient r {approx}> 0.7 at k {approx}tight correlation will enable robust cross-correlation measurement between SZ surveys such as Planck, ACT, and SPT and lensing surveys such as DES and LSST, at {approx}>20{sigma}-100{sigma} level. (2) We propose a tomography technique to convert the measured cross-correlation into the contribution from gas in each redshift bin to the tSZ power spectrum. Uncertainties in gastrophysics may affect the reconstruction at {approx}2% level, due to the {approx}1% impact of gastrophysics on r found in our simulations. However, we find that the same gastrophysics affects the tSZ power spectrum at {approx}40% level, so it is robust to infer the gastrophysics from the reconstructed redshift-resolved contribution.

Shao Jiawei; Zhang Pengjie; Lin Weipeng; Jing Yipeng, E-mail: jwshao@shao.ac.cn [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Nandan Road 80, Shanghai 200030 (China)

2011-04-01T23:59:59.000Z

53

Error matrix in quantum process tomography  

E-Print Network (OSTI)

We discuss characterization of experimental quantum gates by the error matrix, which is similar to the standard process matrix $\\chi$ in the Pauli basis, except the desired unitary operation is factored out, by formally placing it either before or after the error process. The error matrix has only one large element, which is equal to the process fidelity, while other elements are small and indicate imperfections. The imaginary parts of the elements along the left column and/or top row directly indicate the unitary imperfection and can be used to find the needed correction. We discuss a relatively simple way to calculate the error matrix for a composition of quantum gates. Similarly, it is rather straightforward to find the first-order contribution to the error matrix due to the Lindblad-form decoherence. We also discuss a way to identify and subtract the tomography procedure errors due to imperfect state preparation and measurement. In appendices we consider several simple examples of the process tomography and also discuss an intuitive physical interpretation of the Lindblad-form decoherence.

Alexander N. Korotkov

2013-09-25T23:59:59.000Z

54

Dynamic Inversion for Hydrological Process Monitoring with Electrical Resistance Tomography Under Model Uncertainty  

E-Print Network (OSTI)

water content using electrical resistivity tomography, WaterJ. Nitao (1992), Electrical resistivity tomography of vadoseinverse model for electrical resistivity surveys and its

Lehikoinen, A.

2010-01-01T23:59:59.000Z

55

Ultra-high resolution computed tomography imaging  

DOE Patents (OSTI)

A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

2002-01-01T23:59:59.000Z

56

Dynamic tomography with a priori information  

SciTech Connect

We present ''dynamic tomography'' algorithms that allow for the high-resolution, time-resolved imaging of dynamic (i.e., continuously time evolving) complex systems at existing x-ray micro-CT facilities. The behavior of complex systems is constrained by the underlying physics. By exploiting a priori knowledge of the geometry of the physical process being studied to allow the use of sophisticated iterative reconstruction techniques that incorporate constraints, we improve on current frame rates by at least an order of magnitude. This allows time-resolved imaging of previously intractable processes, such as two-phase fluid flow. We present reconstructions from experimental data collected at the Australian National University x-ray micro-CT facility.

Myers, Glenn R.; Kingston, Andrew M.; Varslot, Trond K.; Turner, Michael L.; Sheppard, Adrian P.

2011-07-10T23:59:59.000Z

57

MicroComputed Tomography: Methodology and Applications  

Science Conference Proceedings (OSTI)

Due to the availability of commercial laboratory systems and the emergence of user facilities at synchrotron radiation sources, studies of microcomputed tomography or microCT have increased exponentially. MicroComputed Technology provides a complete introduction to the technology, describing how to use it effectively and understand its results. The first part of the book focuses on methodology, covering experimental methods, data analysis, and visualization approaches. The second part addresses various microCT applications, including porous solids, microstructural evolution, soft tissue studies, multimode studies, and indirect analyses. The author presents a sufficient amount of fundamental material so that those new to the field can develop a relative understanding of how to design their own microCT studies. One of the first full-length references dedicated to microCT, this book provides an accessible introduction to field, supplemented with application examples and color images.

(NWU)

2009-04-02T23:59:59.000Z

58

Positron emission tomography of the heart  

SciTech Connect

Positron emission computed tomography (PCT) represents an important new tool for the noninvasive evaluation and, more importantly, quantification of myocardial performance. Most currently available techniques permit assessment of only one aspect of cardiac function, i.e., myocardial perfusion by gamma scintillation camera imaging with Thallium-201 or left ventricular function by echocardiography or radionuclide angiocardiography. With PCT it may become possible to study all three major segments of myocardial performance, i.e., regional blood flow, mechanical function and, most importantly, myocardial metabolism. Each of these segments can either be evaluated separately or in combination. This report briefly describes the principles and technological advantages of the imaging device, reviews currently available radioactive tracers and how they can be employed for the assessment of flow, function and metabolism; and, lastly, discusses possible applications of PCT for the study of cardiac physiology or its potential role in the diagnosis of cardiac disease.

Schelbert, H.R.; Phelps, M.E.; Kuhl, D.E.

1979-01-01T23:59:59.000Z

59

Passive Network Tomography Using Bayesian Inference  

E-Print Network (OSTI)

this paper, we investigate the problem of identifying lossy links in the interior of the Internet by passively observing the end-to-end performance of existing traffic between a server and its clients. This is in contrast to the previous work on network tomography (e.g., [1]) that has been based on active probing. The key advantage of a passive approach is that it does not introduce wasteful traffic which might perturb the object of inference, i.e., the link loss rates. Moreover, our techniques depend only on knowing the number of lost and successful packets sent to each client rather than the exact loss sequence required by previous techniques such as [1]. While accuracy of link loss rate inference may consequently suffer, our techniques can still pinpoint the trouble spots in the network (e.g., highly lossy links)

Venkata N. Padmanabhan; Lili Qiu; Helen J. Wang

2002-01-01T23:59:59.000Z

60

Feasibility study for mega-electron-volt electron beam tomography  

SciTech Connect

Electron beam tomography is a promising imaging modality for the study of fast technical processes. But for many technical objects of interest x rays of several hundreds of keV energy are required to achieve sufficient material penetration. In this article we report on a feasibility study for fast electron beam computed tomography with a 1 MeV electron beam. The experimental setup comprises an electrostatic accelerator with beam optics, transmission target, and a single x-ray detector. We employed an inverse fan-beam tomography approach with radiographic projections being generated from the linearly moving x-ray source. Angular projections were obtained by rotating the object.

Hampel, U. [Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden (Germany); AREVA Endowed Chair of Imaging Techniques in Energy and Process Engineering, Technische Universitaet Dresden, 01062 Dresden (Germany); Baertling, Y.; Hoppe, D. [Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden (Germany); Kuksanov, N.; Fadeev, S.; Salimov, R. [Budker Institute of Nuclear Physics of Siberian Branch of Russian Academy of Science, Lavrentiev av. 11, Novosibirsk 630090 (Russian Federation)

2012-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators  

Open Energy Info (EERE)

Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators In The Western Great Basin Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators In The Western Great Basin Details Activities (8) Areas (4) Regions (0) Abstract: Body and surface wave tomography are two of the primary methods for estimation of regional scale seismic velocity variations. Seismic velocity is affected by temperature and rock composition in complex ways, but when combined with geologic and structural maps, relative temperature can in some cases be estimated. We present preliminary tomographic models for compressional and shear-wave velocity using local and regional earthquakes recorded by Earthscope Transportable Array stations, network

62

Electrical capacitance volume tomography (ECVT) applied to bubbling fluid beds  

SciTech Connect

These presentation visuals illustrate the apparatus and method for applying Electrical Capacitance Volume Tomography (ECVT) to bubbling fluid beds to their solid fraction and bubble properties. Results are compared to estimated values.

Weber, J., Mei, J.

2012-01-01T23:59:59.000Z

63

Full-3D Waveform Tomography for Southern California | Argonne...  

NLE Websites -- All DOE Office Websites (Extended Search)

Submitted by mkaczmar on October 3, 2012 - 09:19 Authors: Lee, E., Chenm P., Jordan, T.H., Maechling, P.J., Denolle, M., Beroza, G.C. Our full-3D tomography (F3DT) uses...

64

Cerenkov luminescence tomography for in vivo radiopharmaceutical imaging  

Science Conference Proceedings (OSTI)

Cerenkov luminescence imaging (CLI) is a cost-effective molecular imaging tool for biomedical applications of radiotracers. The introduction of Cerenkov luminescence tomography (CLT) relative to planar CLI can be compared to the development of X-ray ...

Jianghong Zhong; Chenghu Qin; Xin Yang; Shuping Zhu; Xing Zhang; Jie Tian

2011-01-01T23:59:59.000Z

65

Satellite Remote Sensing by the Technique of Computed Tomography  

Science Conference Proceedings (OSTI)

Computed tomography is a medical diagnostic technique in which x-ray transmission measurements at numerous angles through the human body are processed by computer to produce cross-sectional pictures of the body. A modification of this technique, ...

Henry E. Fleming

1982-10-01T23:59:59.000Z

66

A Simulation Study of Satellite Emission Computed Tomography  

Science Conference Proceedings (OSTI)

Satellite emission computed tomography retrieves the temperature of the atmosphere from radiances observed at multiple viewing angles and frequencies. To the extent that it provides independent information, the use of multiple viewing angles ...

Ross N. Hoffman; Christopher Grassotti; Ronald G. Isaacs; Thomas J. Kleespies

1989-05-01T23:59:59.000Z

67

From quantum Bayesian inference to quantum tomography  

E-Print Network (OSTI)

We derive an expression for a density operator estimated via Bayesian quantum inference in the limit of an infinite number of measurements. This expression is derived under the assumption that the reconstructed system is in a pure state. In this case the estimation corresponds to an averaging over a generalized microcanonical ensemble of pure states satisfying a set of constraints imposed by the measured mean values of the observables under consideration. We show that via the ``purification'' ansatz, statistical mixtures can also be consistently reconstructed via the quantum Bayesian inference scheme. In this case the estimation corresponds to averaging over the generalized canonical ensemble of states satisfying the given constraints, and the reconstructed density operator maximizes the von Neumann entropy (i.e., this density operator is equal to the generalized canonical density operator which follows from the Jaynes principle of maximum entropy). We study in detail the reconstruction of the spin-1/2 density operator and discuss the logical connection between the three reconstruction schemes, i.e., (1) quantum Bayesian inference, (2) reconstruction via the Jaynes principle of maximum entropy, and (3) discrete quantum tomography.

R. Derka; V. Buzek; G. Adam; P. L. Knight

1997-01-23T23:59:59.000Z

68

Portable Digital Radiography and Computed Tomography Manual  

SciTech Connect

This user manual describes the function and use of the portable digital radiography and computed tomography (DRCT) scanner. The manual gives a general overview of x-ray imaging systems along with a description of the DRCT system. An inventory of the all the system components, organized by shipping container, is also included. In addition, detailed, step-by-step procedures are provided for all of the exercises necessary for a novice user to successfully collect digital radiographs and tomographic images of an object, including instructions on system assembly and detector calibration and system alignment. There is also a short section covering the limited system care and maintenance needs. Descriptions of the included software packages, the DRCT Digital Imager used for system operation, and the DRCT Image Processing Interface used for image viewing and tomographic data reconstruction are given in the appendixes. The appendixes also include a cheat sheet for more experienced users, a listing of known system problems and how to mitigate them, and an inventory check-off sheet suitable for copying and including with the machine for shipment purposes.

Not Available

2007-11-01T23:59:59.000Z

69

Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic Resonance  

NLE Websites -- All DOE Office Websites (Extended Search)

Allan M. Cormack, Computerized Axial Tomography (CAT) Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial tomography, commonly known as CAT scanning, was introduced in 1972. During a CAT scan, a large coil of x-ray tubes rotates around the patient's body, taking x-rays from all angles. A computer integrates all of these x-rays into a single, three-dimensional image on a television screen. The data can be saved on the computer. Allan M. Cormack, a high energy physicist at Tufts University, shared the 1979 Nobel Prize in Physiology and Medicine for his key work in developing the methods for CAT scanners. At the time of development, these methods were widely regarded as the most significant advance in medical radiography since the 1895 discovery of x-rays.

70

Quantum process tomography of a single solid state qubit  

E-Print Network (OSTI)

We present an example of quantum process tomography performed on a single solid state qubit. The qubit used is two energy levels of the triplet state in the Nitrogen-Vacancy defect in Diamond. Quantum process tomography is applied to a qubit which has been allowed to decohere for three different time periods. In each case the process is found in terms of the $\\chi$ matrix representation and the affine map representation. The discrepancy between experimentally estimated process and the closest physically valid process is noted.

M. Howard; J. Twamley; C. Wittmann; T. Gaebel; F. Jelezko; J. Wrachtrup

2005-03-16T23:59:59.000Z

71

Quantum Process Tomography via L1-norm Minimization  

E-Print Network (OSTI)

For an initially well designed but imperfect quantum information system, the process matrix is almost sparse in an appropriate basis. Existing theory and associated computational methods (L1-norm minimization) for reconstructing sparse signals establish conditions under which the sparse signal can be perfectly reconstructed from a very limited number of measurements (resources). Although a direct extension to quantum process tomography of the L1-norm minimization theory has not yet emerged, the numerical examples presented here, which apply L1-norm minimization to quantum process tomography, show a significant reduction in resources to achieve a desired estimation accuracy over existing methods.

Robert L. Kosut

2008-12-23T23:59:59.000Z

72

Positron emission tomography in the evaluation of subdural hematomas  

SciTech Connect

Fifteen patients with 21 subdural effusions were investigated both with transmission computer assisted tomography (CAT) and positron emission tomography (PET). The tracer in the emission studies was /sup 68/Ga-EDTA. Twelve lesions were visualized both with CAT and PET. Five lesions that were negative or doubtful on CAT were visualized with PET, whereas four lesions negative or doubtful on PET were demonstrated by CAT. The two methods complement each other due to the fact that they are based on different mechanisms: CAT mainly on attenuation of the fluid collection. PET on isotope accumulation, particularly in the hematoma membranes.

Ericson, K.; Bergstroem, M.; Eriksson, L.

1980-12-01T23:59:59.000Z

73

Statistical estimation of the quality of quantum-tomography protocols  

SciTech Connect

We present a complete methodology for testing the performances of quantum tomography protocols. The theory is validated by several numerical examples and by the comparison with experimental results achieved with various protocols for whole families of polarization states of qubits and ququarts including pure, mixed, entangled, and separable.

Bogdanov, Yu. I.; Bukeev, I. D. [Institute of Physics and Technology, Russian Academy of Sciences, 117218, Moscow (Russian Federation); Brida, G.; Genovese, M.; Shurupov, A. P. [INRIM, Strada delle Cacce 91 I-10135, Torino (Italy); Kravtsov, K. S. [Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, 119991 (Russian Federation); Kulik, S. P.; Soloviev, A. A. [Faculty of Physics, Moscow State University, 119992, Moscow (Russian Federation); Moreva, E. V. [Moscow National Research Nuclear University ' ' MEPHI' ' , 115409, Moscow (Russian Federation)

2011-10-15T23:59:59.000Z

74

Experimental Cerenkov luminescence tomography of the mouse model with SPECT  

E-Print Network (OSTI)

Experimental Cerenkov luminescence tomography of the mouse model with SPECT imaging validation imaging resulting from Cerenkov radiation has become a motivating topic recently and will potentially open new avenues for the study of small animal imaging. Cerenkov-based optical imaging taken from living

Tian, Jie

75

A fuzzy segmentation method for Computed Tomography images  

Science Conference Proceedings (OSTI)

This paper describes a way of medical image segmentation using an appropriately defined fuzzy clustering method based on a fuzzy similarity relation. The considered relation is defined in terms of the Minkowski metric. A fuzzy similarity relation based ... Keywords: CT, computed tomography, data partitional clustering, fuzzy clustering, fuzzy segmentation, fuzzy similarity relations, image segmentation, medical imaging

Martin Tabakov

2007-04-01T23:59:59.000Z

76

Resistivity Tomography At Silver Peak Area (DOE GTP) | Open Energy  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Resistivity Tomography At Silver Peak Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Single-Well and Cross-Well Resistivity At Silver Peak Area (DOE GTP) Exploration Activity Details Location Silver Peak Area Exploration Technique Single-Well and Cross-Well Resistivity Activity Date Usefulness not indicated DOE-funding Unknown References (1 January 2011) GTP ARRA Spreadsheet Retrieved from "http://en.openei.org/w/index.php?title=Resistivity_Tomography_At_Silver_Peak_Area_(DOE_GTP)&oldid=689883" Categories:

77

Using electrical impedance tomography to map subsurface hydraulic conductivity  

DOE Patents (OSTI)

The use of Electrical Impedance Tomography (EIT) to map subsurface hydraulic conductivity. EIT can be used to map hydraulic conductivity in the subsurface where measurements of both amplitude and phase are made. Hydraulic conductivity depends on at least two parameters: porosity and a length scale parameter. Electrical Resistance Tomography (ERT) measures and maps electrical conductivity (which can be related to porosity) in three dimensions. By introducing phase measurements along with amplitude, the desired additional measurement of a pertinent length scale can be achieved. Hydraulic conductivity controls the ability to flush unwanted fluid contaminants from the surface. Thus inexpensive maps of hydraulic conductivity would improve planning strategies for subsequent remediation efforts. Fluid permeability is also of importance for oil field exploitation and thus detailed knowledge of fluid permeability distribution in three-dimension (3-D) would be a great boon to petroleum reservoir analysts.

Berryman, James G. (Danville, CA); Daily, William D. (Livermore, CA); Ramirez, Abelardo L. (Pleasanton, CA); Roberts, Jeffery J. (Livermore, CA)

2000-01-01T23:59:59.000Z

78

Single electron quantum tomography in quantum Hall edge channels  

E-Print Network (OSTI)

We propose a quantum tomography protocol to measure single electron coherence in quantum Hall edge channels and therefore access for the first time the wave function of single electron excitations propagating in ballistic quantum conductors. Its implementation would open the way to quantitative studies of single electron decoherence and would provide a quantitative tool for analyzing single to few electron sources. We show how this protocol could be implemented using ultrahigh sensitivity noise measurement schemes.

Grenier, Charles; Bocquillon, Erwann; Parmentier, François D; Plaçais, Bernard; Berroir, Jean-Marc; Fève, Gwendal; Degiovanni, Pascal; 10.1088/1367-2630/13/9/093007

2011-01-01T23:59:59.000Z

79

Single electron quantum tomography in quantum Hall edge channels  

E-Print Network (OSTI)

We propose a quantum tomography protocol to measure single electron coherence in quantum Hall edge channels and therefore access for the first time the wave function of single electron excitations propagating in ballistic quantum conductors. Its implementation would open the way to quantitative studies of single electron decoherence and would provide a quantitative tool for analyzing single to few electron sources. We show how this protocol could be implemented using ultrahigh sensitivity noise measurement schemes.

Charles Grenier; Rémy Hervé; Erwann Bocquillon; François D. Parmentier; Bernard Plaçais; Jean-Marc Berroir; Gwendal Fève; Pascal Degiovanni

2010-10-11T23:59:59.000Z

80

In-situ Three Dimensional (3D) X-Ray Synchrotron Tomography of ...  

Science Conference Proceedings (OSTI)

Local measurements of da/dN were possible with the 3D data sets obtained from tomography. In situ measurements of crack opening displacement (COD) were ...

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Development of a seismic tomography system for use on a geotechnical centrifuge.  

E-Print Network (OSTI)

??[Truncated abstract] Seismic tomography has been extensively used in geophysics for different purposes such as geological mapping and prospecting for oil and gas. In geophysics,… (more)

Rammah, Khader Ibrahim

2008-01-01T23:59:59.000Z

82

Understanding Cellulose Through Molecular Simulation and Electron Tomography  

SciTech Connect

High-resolution cellulose crystal structures have been determined from diffraction experiments using large diameter microfibrils as the sample material. However, cellulose microfibrils in plants are much smaller in diameter, and are more difficult to directly examine experimentally. Molecular dynamics simulation combined with quantum chemical calculations can help to elucidate the structure and dynamics of small diameter cellulose microfibrils. These simulation techniques also aid in the interpretation of electron tomography volumetric structural data from maize cell walls, where pretreatment with dilute acid or ammonia reveals microfibril geometry.

Matthews, J.

2013-01-01T23:59:59.000Z

83

Quantum process tomography of a controlled-NOT gate  

E-Print Network (OSTI)

We demonstrate complete characterization of a two-qubit entangling process - a linear optics controlled-NOT gate operating with coincident detection - by quantum process tomography. We use maximum-likelihood estimation to convert the experimental data into a physical process matrix. The process matrix allows accurate prediction of the operation of the gate for arbitrary input states, and calculation of gate performance measures such as the average gate fidelity, average purity and entangling capability of our gate, which are 0.90, 0.83 and 0.73, respectively.

J. L. O'Brien; G. J. Pryde; A. Gilchrist; D. F. V. James; N. K. Langford; T. C. Ralph; A. G. White

2004-02-23T23:59:59.000Z

84

Direct and Parallel Tomography of a Quantum Process  

E-Print Network (OSTI)

As the method to completely characterize quantum dynamical processes, quantum process tomography (QPT) is vitally important for quantum information processing and quantum control, where the faithfulness of quantum devices plays an essential role. Here via weak measurements, we present a new QPT scheme characterized by its directness and parallelism. Comparing with the existing schemes, our scheme needs a simpler state preparation and much fewer experimental setups. Furthermore, each parameter of the quantum process is directly determined from only five experimental values in our scheme, meaning that our scheme is robust against the accumulation of errors.

Yu-Xiang Zhang; Shengjun Wu; Zeng-Bing Chen

2013-09-23T23:59:59.000Z

85

Estimating the risk associated with computerized tomography doses  

SciTech Connect

The largest annual whole- body dose to the US population from man-made radiation is from medical sources. According to the BEIR report, the use of diagnostic x-rays by the medical profession has increased in recent years at an annual rate of 1 to 4%. Risk factors developed by the BEIR committee can be used to estimate the risk to the population due to the exposure incurred through medical radiography. In this paper, these risk factors are employed to obtain an estimate of risk due to radiation exposure from computerized tomography (CT).

Yalcintas, M.G.; Leggett, R.W.; Dunning, D.E.; Nalcioglu, O.

1979-01-01T23:59:59.000Z

86

Spatial emission tomography reconstruction using Pitman-Yor process  

SciTech Connect

In this paper, we address the problem of emission tomography spatial reconstruction in three dimensions following a Bayesian nonparametric approach. Our model makes use of a generalization of the Dirichlet process called Pitman-Yor process. The problem in this approach is to deal with the infinite representation of the distribution in the inference. So we propose an efficient Markov Chain Monte-Carlo sampling scheme which is able to generate samples from the posterior distribution of the activity distribution. An application to 3D-PET reconstruction is presented.

Fall, Mame Diarra; Mohammad-Djafari, Ali [L2S, Supelec, 3 rue Joliot-Curie, F-91192 Gif-sur-Yvette cedex (France); Barat, Eric [CEA-LIST, LPSS, CEA-Saclay, F-91191 Gif-sur-Yvette (France); Comtat, Claude [SHFJ, CEA/DSV/I2BM, F-91401 Orsay (France)

2009-12-08T23:59:59.000Z

87

Simultaneous CT and SPECT tomography using CZT detectors  

DOE Patents (OSTI)

A method for simultaneous transmission x-ray computed tomography (CT) and single photon emission tomography (SPECT) comprises the steps of: injecting a subject with a tracer compound tagged with a .gamma.-ray emitting nuclide; directing an x-ray source toward the subject; rotating the x-ray source around the subject; emitting x-rays during the rotating step; rotating a cadmium zinc telluride (CZT) two-sided detector on an opposite side of the subject from the source; simultaneously detecting the position and energy of each pulsed x-ray and each emitted .gamma.-ray captured by the CZT detector; recording data for each position and each energy of each the captured x-ray and .gamma.-ray; and, creating CT and SPECT images from the recorded data. The transmitted energy levels of the x-rays lower are biased lower than energy levels of the .gamma.-rays. The x-ray source is operated in a continuous mode. The method can be implemented at ambient temperatures.

Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Lubbock, TX); Simpson, Michael L. (Knoxville, TN); Britton, Jr., Charles L. (Alcoa, TN)

2002-01-01T23:59:59.000Z

88

Temporal and spatial blood information estimation using Bayesian ICA in dynamic cerebral positron emission tomography  

Science Conference Proceedings (OSTI)

Positron emission tomography (PET) is a nuclear medicine technique that provides tomographic images of the distribution of positron-emitting radiopharmaceuticals. We have previously proposed a method for estimating an input blood curve based on a standard ... Keywords: Arterial blood sampling, Blood volume image, Ensemble learning, Independent component analysis, Positron emission tomography

Mika Naganawa; Yuichi Kimura; Kenji Ishii; Keiichi Oda; Kiichi Ishiwata

2007-09-01T23:59:59.000Z

89

WIND TOMOGRAPHY IN BINARY SYSTEMS O.Knill, R.Dgani and M.Vogel  

E-Print Network (OSTI)

WIND TOMOGRAPHY IN BINARY SYSTEMS O.Knill, R.Dgani and M.Vogel ETH-Zurich, CH-8092, Switzerland method is particularly suitable for determining the velocity laws of stellar winds. 1. WIND TOMOGRAPHY AND ABEL'S INTEGRAL Binary systems in which a compact, point-like radiation source shines through the wind

Knill, Oliver

90

All-optical quantitative framework for bioluminescence tomography with non-contact measurement  

Science Conference Proceedings (OSTI)

In this contribution, we present an all-optical quantitative framework for bioluminescence tomography with non-contact measurement. The framework is comprised of four indispensable steps: extraction of the geometrical structures of the subject, light ... Keywords: All-optical, bioluminescence tomography, non-contact, quantitative framework, surface extraction

Xue-Li Chen; Heng Zhao; Xiao-Chao Qu; Duo-Fang Chen; Xiao-Rui Wang; Ji-Min Liang

2012-02-01T23:59:59.000Z

91

Whole-Body Cerenkov Luminescence Tomography with the Finite Element SP3 Method  

E-Print Network (OSTI)

Whole-Body Cerenkov Luminescence Tomography with the Finite Element SP3 Method JIANGHONG ZHONG, JIE Bai oversaw the review of this article. Abstract--Generation of an accurate Cerenkov luminescence-active approach toward whole-body Cerenkov luminescence tomography. The finite element framework employs

Tian, Jie

92

Microwave tomography for breast cancer detection on Cell broadband engine processors  

Science Conference Proceedings (OSTI)

Microwave tomography (MT) is a safe screening modality that can be used for breast cancer detection. The technique uses the dielectric property contrasts between different breast tissues at microwave frequencies to determine the existence of abnormalities. ... Keywords: Breast cancer detection, Cell BE processor, Finite-difference time-domain (FDTD), Microwave tomography (MT)

Meilian Xu; Parimala Thulasiraman; Sima Noghanian

2012-09-01T23:59:59.000Z

93

Using computerized tomography to determine ionospheric structures. Part 1, Notivation and basic approaches  

SciTech Connect

Properties of the ionosphere are reviewed along with its correlations with other geophysical phenomena and with applications of ionospheric studies to communication, navigation, and surveillance systems. Computer tomography is identified as a method to determine the detailed, three-dimensional distribution of electron density within the ionosphere. Several tomography methods are described, with a basic approach illustrated by an example. Limitations are identified.

Vittitoe, C.N.

1993-08-01T23:59:59.000Z

94

Clinical cardiac positron emission tomography: State of the art  

SciTech Connect

Cardiac positron emission tomography (PET) has evolved rapidly from a relatively esoteric research tool into clinical applications providing unique, quantitative information on myocardial perfusion, metabolism, and cell membrane function and having a potentially significant impact on cardiovascular medicine. Although there are many different positron radionuclides for imaging diverse myocardial behavior, three radionuclides have reached accepted clinical utility. Cardiac PET using nitrogen-13-ammonia, rubidium-82, and fluoro-18-deoxyglucose has proved accurate and definitive in multiple university and private-practice sites for diagnosing and assessing severity and location of coronary artery disease in symptomatic or asymptomatic patients, for identifying injured but viable myocardium potentially salvageable by revascularization, and for ruling out clinically significant coronary artery stenosis with a high specificity in patients who might otherwise undergo coronary arteriography to document the absence of significant disease. 89 references.

Gould, K.L. (Division of Cardiology, University of Texas Health Science Center, Houston (United States))

1991-09-01T23:59:59.000Z

95

Functional Substitution Methods in Optimization for Bayesian Tomography  

E-Print Network (OSTI)

1 Bayesian tomographic reconstruction algorithms generally require the efficient optimization of a functional of many variables. In this setting as well as many other optimization tasks, functional substitution (FS) has been widely applied to simplify each step of the iterative process. The function to be minimized is replaced locally by an approximation having a more easily manipulated form, e.g. quadratic, but which maintains sufficient similarity to descend the true functional while computing only the substitute. In this paper, we provide two new applications of FS methods in iterative coordinate descent for Bayesian tomography. The first is a modification of our recently proposed coordinate descent algorithm with 1-D Newton-Raphson approximations to an alternative quadratic which allows convergence to be proven easily. In simulations we find essentially no difference in convergence speed between the two techniques. We also present a new algorithm which exploits the FS method to all...

Jun Zheng; Suhail Saquib; Ken Sauer; Charles Bouman

1997-01-01T23:59:59.000Z

96

Ultrafast three-dimensional x-ray computed tomography  

SciTech Connect

X-ray computed tomography (CT) is a well established visualization technique in medicine and nondestructive testing. However, since CT scanning requires sampling of radiographic projections from different viewing angles, common CT systems with mechanically moving parts are too slow for dynamic imaging, for instance of multiphase flows or live animals. Here, we introduce an ultrafast three-dimensional x-ray CT method based on electron beam scanning, which achieves volume rates of 500 s{sup -1}. Primary experiments revealed the capability of this method to recover the structure of phase boundaries in gas-solid and gas-liquid two-phase flows, which undergo three-dimensional structural changes in the millisecond scale.

Bieberle, Martina; Barthel, Frank; Hampel, Uwe [Institute of Safety Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden (Germany); Menz, Hans-Juergen; Mayer, Hans-Georg [Institute of Nuclear Technology and Energy Systems, University of Stuttgart, 70569 Stuttgart (Germany)

2011-01-17T23:59:59.000Z

97

Electrical resistance tomography from measurements inside a steel cased borehole  

DOE Patents (OSTI)

Electrical resistance tomography (ERT) produced from measurements taken inside a steel cased borehole. A tomographic inversion of electrical resistance measurements made within a steel casing was then made for the purpose of imaging the electrical resistivity distribution in the formation remotely from the borehole. The ERT method involves combining electrical resistance measurements made inside a steel casing of a borehole to determine the electrical resistivity in the formation adjacent to the borehole; and the inversion of electrical resistance measurements made from a borehole not cased with an electrically conducting casing to determine the electrical resistivity distribution remotely from a borehole. It has been demonstrated that by using these combined techniques, highly accurate current injection and voltage measurements, made at appropriate points within the casing, can be tomographically inverted to yield useful information outside the borehole casing.

Daily, William D. (Livermore, CA); Schenkel, Clifford (Walnut Creek, CA); Ramirez, Abelardo L. (Pleasanton, CA)

2000-01-01T23:59:59.000Z

98

Determination of Internal Target Volume From a Single Positron Emission Tomography/Computed Tomography Scan in Lung Cancer  

SciTech Connect

Purpose: The use of four-dimensional computed tomography (4D-CT) to determine the tumor internal target volume (ITV) is usually characterized by high patient radiation exposure. The objective of this study was to propose and evaluate an approach that relies on a single static positron emission tomography (PET)/CT scan to determine the ITV, thereby eliminating the need for 4D-CT and thus reduce patient radiation dose. Methods and Materials: The proposed approach is based on the concept that the observed PET image is the result of a joint convolution of an ideal PET image (free from motion and partial volume effect) with a motion-blurring kernel (MBK) and partial volume effect. In this regard, the MBK and tumor ITV are then estimated from the deconvolution of this joint model. To test this technique, phantom and patient studies were performed using different sphere/tumor sizes and motion trajectories. In all studies, a 4D-CT and a PET/CT image of the sphere/tumor were acquired. The ITV from the proposed technique was then compared to the maximum intensity projection (MIP) volume of the 4D-CT images. A Dice coefficient of the two volumes was calculated to represent the similarity between the two ITVs. Results: The average ITVs of the proposed technique were 97.2% {+-} 0.3% and 81.0% {+-} 16.7% similar to the MIP volume in the phantom and patient studies, respectively. The average dice coefficients were 0.87 {+-} 0.05 and 0.73 {+-} 0.16, respectively, for the two studies. Conclusion: Using the proposed approach, a single static PET/CT scan has the potential to replace a 4D-CT to determine the tumor ITV. This approach has the added advantage of reducing patient radiation exposure and determining the tumor MBK compared to 4D-CT/MIP-CT.

Chang Guoping; Chang Tingting [Department of Electrical and Computer Engineering, Rice University, Houston, Texas (United States); Pan Tinsu [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Clark, John W. [Department of Electrical and Computer Engineering, Rice University, Houston, Texas (United States); Mawlawi, Osama R., E-mail: OMawlawi@mdanderson.org [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2012-05-01T23:59:59.000Z

99

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance  

NLE Websites -- All DOE Office Websites (Extended Search)

Non-medical Uses of Computed Tomography (CT) Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Computed Tomography (CT) Scanner CT Scanner - Courtesy Stanford University Department of Energy Resources Engineering Computed tomography (CT) and Nuclear Magnetic Resonance (NMR) have been used to resolve industrial problems, for materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts before their use, resulting in greater reliability and greater safety for workers; to identify the presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non-destructive testing and quality control of fresh fruits and vegetables, enhancing the safety of food. These benefits of non-medical uses of CT and NMR contribute to the economy and improve people's lives.

100

Peak Tracking by Simultaneous Inversion: Toward a One-Step Acoustic Tomography Analysis  

Science Conference Proceedings (OSTI)

A number of geophysical observing techniques, including ocean acoustic tomography, obtain sequences of records of which the observed relative maxima (“peaks”) are used to infer properties of the system via inversions. Traditionally, these peaks ...

Uwe Send

1996-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Advances in Optical Coherence Tomography and Microscopy for endoscopic applications and functional neuroimaging  

E-Print Network (OSTI)

Optical Coherence Tomography (OCT) is a developing medical imaging technology that generates micron resolution cross-sectional images of subsurface internal tissue structure in situ and in real time, without the need to ...

Aguirre, Aaron Dominic, 1977-

2008-01-01T23:59:59.000Z

102

Applications of Fourier Domain Mode Locked lasers for optical coherence tomography imaging  

E-Print Network (OSTI)

Optical coherence tomography (OCT) is a micrometer-resolution imaging technique that produces cross-sectional images of sample microstructure by measuring the amplitude and echo time delay of backscattered light. OCT imaging ...

Adler, Desmond Christopher, 1978-

2009-01-01T23:59:59.000Z

103

ARM - Field Campaign - Ground-based Cloud Tomography Experiment at SGP  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsGround-based Cloud Tomography Experiment at SGP govCampaignsGround-based Cloud Tomography Experiment at SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Ground-based Cloud Tomography Experiment at SGP 2009.05.26 - 2009.07.17 Lead Scientist : Dong Huang For data sets, see below. Description Knowledge of 3D cloud properties is pressingly needed in many research fields. One of the problems encountered when trying to represent 3D cloud fields in numerical models is that the existing techniques cannot provide necessary observations at the required spatial scale and resolution. We tested a new promising technique for measuring 3D cloud microphysical structure, called cloud microwave tomography, at the Southern Great Plains (SGP) site for one month in late April 2009. Five microwave scanning

104

Atom Probe Tomography Analysis of Solute Clustering in Al-Mg-Si ...  

Science Conference Proceedings (OSTI)

Contributions of Atom Probe Tomography to the Understanding of Steels · Control of p-n ... Relationships in a Series of Co-Cr-Cu-Fe-Ni-Al High Entropy Alloys.

105

One-Step Analysis of Nonlinear Traveltime Data in Ocean Acoustic Tomography  

Science Conference Proceedings (OSTI)

A new approach based on statistical estimation is proposed for the analysis of tomographic traveltime data in cases of significant nonlinear dependence of the traveltimes on the sound-speed variations. Traditional tomography schemes based on ...

E. K. Skarsoulis; U. Send

2000-02-01T23:59:59.000Z

106

A Planetary Wave Analysis Using the Acoustic and Conventional Arrays in the 1981 Ocean Tomography Experiment  

Science Conference Proceedings (OSTI)

Using the maximum likelihood estimation method, quasi-geostrophic wave solutions are fitted to the observations of the 1981 Ocean Acoustic Tomography Experiment. The experiment occupied a 300 km square area centered at 26°N, 70°W over a duration ...

Ching-Sang Chiu; Yves Desaubies

1987-08-01T23:59:59.000Z

107

NIBART: A New Interval Based Algebraic Reconstruction Technique for Error Quantification of Emission Tomography Images  

Science Conference Proceedings (OSTI)

This article presents a new algebraic method for reconstructing emission tomography images. This approach is mostly an interval extension of the conventional SIRT algorithm. One of the main characteristic of our approach is that the reconstructed activity ...

Olivier Strauss; Abdelkabir Lahrech; Agnès Rico; Denis Mariano-Goulart; Benoît Telle

2009-10-01T23:59:59.000Z

108

Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard tissues imaging  

E-Print Network (OSTI)

Non-linear inversion modeling for Ultrasound Computer Tomography: transition from soft to hard, the tomographic procedure used is adapted to broadband data acquired in scattering configurations while, Iterative Approximation, Soft Tissues Imaging, Hard Tissues Imaging, Breast, Bones 1. INTRODUCTION

109

Evolution of upper mantle beneath East Asia and the Tibetan Plateau from P-wave tomography  

E-Print Network (OSTI)

The main objective of the research presented in this thesis is to improve our understanding for the evolution of the upper mantle beneath East Asia and the Tibetan Plateau through high resolution P-wave tomography. The ...

Li, Chang, Ph.D. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

110

Fuel Reliability Program: Assessment of Nuclear Fuel Pellets Using X-Ray Tomography  

Science Conference Proceedings (OSTI)

This EPRI technical report describes a feasibility study involving the application of X-ray tomography as an inspection technique to detect flaws on the surface of uranium pellets in nuclear fuel rods. The objective was to develop and evaluate a system for tomographic imaging of fuel pellets inside fuel rods that uses fast algorithms for analysis of each slice of the reconstructed image for detection of abnormalities in the pellet. The report describes the fundamentals of X-ray tomography and ...

2013-02-22T23:59:59.000Z

111

Imaging atherosclerotic plaque inflammation with [18F]- fluorodeoxyglucose positron emission tomography  

E-Print Network (OSTI)

of tracer CI Confidence interval CO2 Carbon dioxide CRP C-reactive protein CT Computed tomography DPM Decays per minute eNOS Endothelial nitric oxide synthase EDTA Ethylene diamine tetra-acetic acid ETL Echo train... rabbit p Probability PBMC Peripheral blood mononuclear cells PBS Phosphate-buffered saline PDGF Platelet-derived growth factor PDW Proton density-weighted PET Positron emission tomography PK11195 1-(2-chlorophenyl...

Rudd, James H. F.

2003-10-07T23:59:59.000Z

112

Parallelizable Bayesian Tomography Algorithms with Rapid, Guaranteed Convergence  

E-Print Network (OSTI)

Bayesian tomographic reconstruction algorithms generally require the efficient optimization of a functional of many variables. In this setting, as well as in many other optimization tasks, functional substitution (FS) has been widely applied to simplify each step of the iterative process. The function to be minimized is replaced locally by an approximation having a more easily manipulated form, e.g., quadratic, but which maintains sufficient similarity to descend the true functional while computing only the substitute. In this paper, we provide two new applications of FS methods in iterative coordinate descent for Bayesian tomography. The first is a modification of our coordinate descent algorithm with one-dimensional (1-D) Newton--Raphson approximations to an alternative quadratic which allows convergence to be proven easily. In simulations, we find essentially no difference in convergence speed between the two techniques. We also present a new algorithm which exploits the FS method to allow parallel updates of arbitrary sets of pixels using computations similar to iterative coordinate descent. The theoretical potential speed up of parallel implementations is nearly linear with the number of processors if communication costs are neglected.

Jun Zheng; Suhail S. Saquib; Ken Sauer; Charles A. Bouman

2000-01-01T23:59:59.000Z

113

Digital Radiography and Computed Tomography (DRCT) Product Improvement Plan (PIP)  

SciTech Connect

The Idaho National Laboratory (INL) has been developing and deploying x-ray inspection systems for chemical weapons containers for the past 12 years under the direction of the Project Manager for Non-Stockpile Chemical Materiel (PMNSCM). In FY-10 funding was provided to advance the capabilities of these systems through the DRCT (Digital Radiography and Computed Tomography) Product Improvement Plan (PIP), funded by the PMNSCM. The DRCT PIP identified three research tasks; end user study, detector evaluation and DRCT/PINS integration. Work commenced in February, 2010. Due to the late start and the schedule for field inspection of munitions at various sites, it was not possible to spend sufficient field time with operators to develop a complete end user study. We were able to interact with several operators, principally Mr. Mike Rowan who provided substantial useful input through several discussions and development of a set of field notes from the Pueblo, CO field mission. We will be pursuing ongoing interactions with field personnel as opportunities arise in FY-11.

Tim Roney; Bob Pink; Karen Wendt; Robert Seifert; Mike Smith

2010-12-01T23:59:59.000Z

114

Positron Emission Tomography Detector Development for Plant Biology  

Science Conference Proceedings (OSTI)

There are opportunities for the development of new tools to advance plant biology research through the use of radionuclides. Thomas Jefferson National Accelerator Facility, Duke University, West Virginia University and the University of Maryland are collaborating on the development of radionuclide imaging technologies to facilitate plant biology research. Biological research into optimizing plant productivity under various environmental constraints, biofuel and carbon sequestration research are areas that could potentially benefit from new imaging technologies. Using 11CO2 tracers, the investigators at Triangle University Nuclear Laboratory / Duke University Phytotron are currently researching the dynamical responses of plants to environmental changes forecasted from increasing greenhouse trace gases involved in global change. The biological research primary focus is to investigate the impact of elevated atmospheric CO2 and nutrients limitation on carbon and nitrogen dynamics in plants. We report here on preliminary results of 11CO2 plant imaging experiments involving barley plants using Jefferson Lab dual planar positron emission tomography detectors to image 11CO2 in live barley plants. New detector designs will be developed based on the preliminary studies reported here and further planned.

Weisenberger, A G; McKisson, J; Stolin, A; Zorn, C; Howell, C R; Crowell, A S; Reid, C D; Majewski, S

2010-01-01T23:59:59.000Z

115

Imaging algorithms for geophysical applications of impedance tomography  

SciTech Connect

The methods of impedance tomography may be employed to obtain images of subsurface electrical and conductivity variations. For practical reasons, voltages and currents are usually applied at locations on the ground surface or down a limited number of boreholes, but almost never over the entire surface of the region being investigated. The geophysical inversion process can be facilitated by constructing algorithms adopted to these particular geometries and to the lack of complete surface data. In this paper we assume that the fluctuations in conductivity are small compared to the background value. The imaging of these fluctuations is carried out exactly within the constraints imposed by the problem geometry. Several possible arrangements of injection and monitoring electrodes are considered. In two dimensions include: Cross-line geometry, current input along one line (borehole) and measurements along a separate parallel line. Single-line geometry, injection and monitoring using the same borehole. Surface reflection geometry, all input and measurement along the ground surface. Theoretical and practical limitations on the image quality produced by the algorithms are discussed. They are applied to several sets of simulated data, and the images produced are displayed and analyzed.

Witten, A.J. (Oak Ridge National Lab., TN (United States)); Molyneux, J.E. (Widener Univ., Dept. of Mechanical Engineering, Chester, PA (United States))

1992-06-02T23:59:59.000Z

116

Using electrical resistance tomography to map subsurface temperatures  

DOE Patents (OSTI)

A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations.

Ramirez, Abelardo L. (Pleasanton, CA); Chesnut, Dwayne A. (San Francisco, CA); Daily, William D. (Livermore, CA)

1994-01-01T23:59:59.000Z

117

Using electrical resistance tomography to map subsurface temperatures  

DOE Patents (OSTI)

A method is provided for measuring subsurface soil or rock temperatures remotely using electrical resistivity tomography (ERT). Electrical resistivity measurements are made using electrodes implanted in boreholes driven into the soil and/or at the ground surface. The measurements are repeated as some process changes the temperatures of the soil mass/rock mass. Tomographs of electrical resistivity are calculated based on the measurements using Poisson's equation. Changes in the soil/rock resistivity can be related to changes in soil/rock temperatures when: (1) the electrical conductivity of the fluid trapped in the soil's pore space is low, (2) the soil/rock has a high cation exchange capacity and (3) the temperature changes are sufficiently high. When these three conditions exist the resistivity changes observed in the ERT tomographs can be directly attributed to changes in soil/rock temperatures. This method provides a way of mapping temperature changes in subsurface soils remotely. Distances over which the ERT method can be used to monitor changes in soil temperature range from tens to hundreds of meters from the electrode locations. 1 fig.

Ramirez, A.L.; Chesnut, D.A.; Daily, W.D.

1994-09-13T23:59:59.000Z

118

Electrical resistance tomography using steel cased boreholes as electrodes  

DOE Patents (OSTI)

An electrical resistance tomography method is described which uses steel cased boreholes as electrodes. The method enables mapping the electrical resistivity distribution in the subsurface from measurements of electrical potential caused by electrical currents injected into an array of electrodes in the subsurface. By use of current injection and potential measurement electrodes to generate data about the subsurface resistivity distribution, which data is then used in an inverse calculation, a model of the electrical resistivity distribution can be obtained. The inverse model may be constrained by independent data to better define an inverse solution. The method utilizes pairs of electrically conductive (steel) borehole casings as current injection electrodes and as potential measurement electrodes. The greater the number of steel cased boreholes in an array, the greater the amount of data is obtained. The steel cased boreholes may be utilized for either current injection or potential measurement electrodes. The subsurface model produced by this method can be 2 or 3 dimensional in resistivity depending on the detail desired in the calculated resistivity distribution and the amount of data to constrain the models. 2 figs.

Daily, W.D.; Ramirez, A.L.

1999-06-22T23:59:59.000Z

119

Electrical resistance tomography using steel cased boreholes as electrodes  

DOE Patents (OSTI)

An electrical resistance tomography method using steel cased boreholes as electrodes. The method enables mapping the electrical resistivity distribution in the subsurface from measurements of electrical potential caused by electrical currents injected into an array of electrodes in the subsurface. By use of current injection and potential measurement electrodes to generate data about the subsurface resistivity distribution, which data is then used in an inverse calculation, a model of the electrical resistivity distribution can be obtained. The inverse model may be constrained by independent data to better define an inverse solution. The method utilizes pairs of electrically conductive (steel) borehole casings as current injection electrodes and as potential measurement electrodes. The greater the number of steel cased boreholes in an array, the greater the amount of data is obtained. The steel cased boreholes may be utilized for either current injection or potential measurement electrodes. The subsurface model produced by this method can be 2 or 3 dimensional in resistivity depending on the detail desired in the calculated resistivity distribution and the amount of data to constain the models.

Daily, William D. (Livermore, CA); Ramirez, Abelardo L. (Pleasanton, CA)

1999-01-01T23:59:59.000Z

120

A generic, geometric cocalibration method for a combined system of fluorescence molecular tomography and microcomputed tomography with arbitrarily shaped objects  

Science Conference Proceedings (OSTI)

Purpose: A combined system of fluorescence molecular tomography and microcomputed tomography (FMT and mCT) can provide molecular and anatomical information of small animals in a single study with intrinsically coregistered images. The anatomical information provided by the mCT subsystem is commonly used as a reference to locate the fluorophore distribution or as a priori structural information to improve the performance of FMT. Therefore, the transformation between the coordinate systems of the subsystem needs to be determined in advanced. Methods: A cocalibration method for the combined system of FMT and mCT is proposed. First, linear models are adopted to describe the galvano mirrors and the charge-coupled device (CCD) camera in the FMT subsystem. Second, the position and orientation of the galvano mirrors are determined with the input voltages of the galvano mirrors and the markers, whose positions are predetermined. The position, orientation and normalized pixel size of the CCD camera are obtained by analysing the projections of a point-like marker at different positions. Finally, the orientation and position of sources and the corresponding relationship between the detectors and their projections on the image plane are predicted. Because the positions of the markers are acquired with mCT, the registration of the FMT and mCT could be realized by direct image fusion. Results: The accuracy and consistency of this method in the presence of noise is evaluated by computer simulation. Next, a practical implementation for an experimental FMT and mCT system is carried out and validated. The maximum prediction error of the source positions on the surface of a cylindrical phantom is within 0.375 mm and that of the projections of a point-like marker is within 0.629 pixel. Finally, imaging experiments of the fluorophore distribution in a cylindrical phantom and a phantom with a complex shape demonstrate the feasibility of the proposed method. Conclusions: This method is universal in FMT and mCT, which could be performed with no restriction on the system geometry, calibration phantoms or imaging objects.

Fu Jianwei; Yang Xiaoquan; Wang Kan; Luo Qingming; Gong Hui [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074 (China) and Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074 (China); Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074 (China); Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074 (China) and Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074 (China)

2011-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Pretreatment Staging Positron Emission Tomography/Computed Tomography in Patients With Inflammatory Breast Cancer Influences Radiation Treatment Field Designs  

SciTech Connect

Purpose: Positron emission tomography/computed tomography (PET/CT) is increasingly being utilized for staging of inflammatory breast cancer (IBC). The purpose of this study was to define how pretreatment PET/CT studies affected postmastectomy radiation treatment (PMRT) planning decisions for IBC. Methods and Materials: We performed a retrospective analysis of 62 patients diagnosed with IBC between 2004 and 2009, who were treated with PMRT in our institution and who had a staging PET/CT within 3 months of diagnosis. Patients received a baseline physical examination, staging mammography, ultrasonographic examination of breast and draining lymphatics, and chest radiography; most patients also had a bone scan (55 patients), liver imaging (52 patients), breast MRI (46 patients), and chest CT (25 patients). We compared how PET/CT findings affected PMRT, assuming that standard PMRT would target the chest wall, level III axilla, supraclavicular fossa, and internal mammary chain (IMC). Any modification of target volumes, field borders, or dose prescriptions was considered a change. Results: PET/CT detected new areas of disease in 27 of the 62 patients (44%). The areas of additional disease included the breast (1 patient), ipsilateral axilla (1 patient), ipsilateral supraclavicular (4 patients), ipsilateral infraclavicular (1 patient), ipsilateral IMC (5 patients), ipsilateral subpectoral (3 patients), mediastinal (8 patients), other distant/contralateral lymph nodes (15 patients), or bone (6 patients). One patient was found to have a non-breast second primary tumor. The findings of the PET/CT led to changes in PMRT in 11 of 62 patients (17.7%). These changes included additional fields in 5 patients, adjustment of fields in 2 patients, and higher doses to the supraclavicular fossa (2 patients) and IMC (5 patients). Conclusions: For patients with newly diagnosed IBC, pretreatment PET/CT provides important information concerning involvement of locoregional lymph nodes, mediastinal lymph nodes, and unsuspected sites of distant metastasis. This information is important in the design of radiotherapy treatment fields and, therefore, we recommend that PET/CT be a component of initial staging for IBC.

Walker, Gary V. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Niikura, Naoki [Department of Breast and Endocrine Surgery, Tokai University School of Medicine, Kanagawa (Japan)] [Department of Breast and Endocrine Surgery, Tokai University School of Medicine, Kanagawa (Japan); Yang Wei [Department of Diagnostic Radiology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Diagnostic Radiology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rohren, Eric [Department of Nuclear Medicine, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Nuclear Medicine, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Valero, Vicente [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Woodward, Wendy A. [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Alvarez, Ricardo H. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lucci, Anthony [Department of Surgical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Surgical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Ueno, Naoto T. [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Breast Medical Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A., E-mail: tbuchhol@mdanderson.org [Department of Radiation Oncology, Morgan Welch Inflammatory Breast Cancer Clinic, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2012-08-01T23:59:59.000Z

122

Tomography of the Reionization Epoch with Multifrequency CMB Observations  

E-Print Network (OSTI)

We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise ratio for the detection of the signal introduced in the CMB by resonant scattering off metals at the end of the Dark Ages. We take into account systematics associated to inter-channel calibration, PSF reconstruction errors and innacurate foreground removal. We develop an algorithm to optimally extract the signal generated by metals during reionisation and to remove accurately the contamination due to the thermal Sunyaev-Zel'dovich effect. Although demanding levels of foreground characterisation and control of systematics are required, they are very distinct from those encountered in HI-21cm studies and CMB polarization, and this fact encourages the study of resonant scattering off metals as an alternative way of conducting tomography of the reionisation epoch. An ACT-like experiment with optimistic assumtions on systematic effects, and looking at clean regions of the sky, can detect changes of 3%-12% (95% c.l.) of the OIII abundance (with respect its solar value) in the redshift range $z\\in$ [12,22], for reionization redshift $z_{\\rm re}>10$. However, for $z_{\\rm re} solar value in the redshift range $z\\in$ [5.5,9], (95% c.l.). These constraints assume that inter-channel calibration is accurate down to one part in $10^{4}$, which constitutes the most critical technical requirement of this method, but still achievable with current technology.

Carlos Hernandez-Monteagudo; Licia Verde; Raul Jimenez

2006-04-14T23:59:59.000Z

123

In vivo breast sound-speed imaging with ultrasound tomography  

Science Conference Proceedings (OSTI)

We discuss a bent-ray ultrasound tomography algorithm with total-variation (TV) regularization. We have applied this algorithm to 61 in vivo breast datasets collected with our in-house clinical prototype for imaging sound-speed distributions in the breast. Our analysis showed that TV regularization could preserve sharper lesion edges than the classic Tikhonov regularization. Furthermore, the image quality of our TV bent-ray sound-speed tomograms was superior to that of the straight-ray counterparts for all types of breasts within BI-RADS density categories 1-4. For all four breast types from fatty to dense, the improvements for average sharpness (in the unit of (m{center_dot} s) {sup -1}) of lesion edges in our TV bent-ray tomograms are between 2.1 to 3.4 fold compared to the straight ray tomograms. Reconstructed sound-speed tomograms illustrated that our algorithm could successfully image fatty and glandular tissues within the breast. We calculated the mean sound-speed values for fatty tissue and breast parenchyma as 1422 {+-} 9 mls (mean{+-} SD) and1487 {+-} 21 mls, respectively. Based on 32 lesions in a cohort of 61 patients, we also found that the mean sound-speed for malignant breast lesions (1548{+-}17 mls) was higher, on average, than that of benign ones (1513{+-}27 mls) (one-sided p

Huang, Lianjie [Los Alamos National Laboratory; Li, Cuiping [KARMANOS CANCER INSTITUTE; Duric, Neb [KARMANOS CANCER INSTITUTE; Littrup, Peter [KARMONOS CANCER INSTITUTE

2009-01-01T23:59:59.000Z

124

THE ATTENUATED RADON TRANSFORM: APPLICATION TO SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY IN THE PRESENCE OF A VARIABLE ATTENUATING MEDIUM  

E-Print Network (OSTI)

section imaging of radionuclide distributions in heart,the myocardium ivith radionuclides, Radiology, 125 (1977),attenuation correction in radionuclide computed tomography,

Gullberg, Grant T.

2013-01-01T23:59:59.000Z

125

Positron Emission Tomography/Computed Tomography-Guided Intensity-Modulated Radiotherapy for Limited-Stage Small-Cell Lung Cancer  

Science Conference Proceedings (OSTI)

Purpose: Omitting elective nodal irradiation from planning target volumes does not compromise outcomes in patients with non-small-cell lung cancer, but whether the same is true for those with limited-stage small-cell lung cancer (LS-SCLC) is unknown. Therefore, in the present study, we sought to determine the clinical outcomes and the frequency of elective nodal failure in patients with LS-SCLC staged using positron emission tomography/computed tomography and treated with involved-field intensity-modulated radiotherapy. Methods and Materials: Between 2005 and 2008, 60 patients with LS-SCLC at our institution underwent disease staging using positron emission tomography/computed tomography before treatment using an intensity-modulated radiotherapy plan in which elective nodal irradiation was intentionally omitted from the planning target volume (mode and median dose, 45 Gy in 30 fractions; range, 40.5 Gy in 27 fractions to 63.8 Gy in 35 fractions). In most cases, concurrent platinum-based chemotherapy was administered. We retrospectively reviewed the clinical outcomes to determine the overall survival, relapse-free survival, and failure patterns. Elective nodal failure was defined as recurrence in initially uninvolved hilar, mediastinal, or supraclavicular nodes. Survival was assessed using the Kaplan-Meier method. Results: The median age of the study patients at diagnosis was 63 years (range, 39-86). The median follow-up duration was 21 months (range, 4-58) in all patients and 26 months (range, 4-58) in the survivors. The 2-year actuarial overall survival and relapse-free survival rate were 58% and 43%, respectively. Of the 30 patients with recurrence, 23 had metastatic disease and 7 had locoregional failure. We observed only one isolated elective nodal failure. Conclusions: To our knowledge, this is the first study to examine the outcomes in patients with LS-SCLC staged with positron emission tomography/computed tomography and treated with definitive intensity-modulated radiotherapy. In these patients, elective nodal irradiation can be safely omitted from the planning target volume for the purposes of dose escalation and toxicity reduction.

Shirvani, Shervin M.; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Heymach, John V.; Fossella, Frank V. [Department of Thoracic/Head and Neck Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

2012-01-01T23:59:59.000Z

126

Time-dependent seismic tomography and its application to the Coso  

Open Energy Info (EERE)

and its application to the Coso and its application to the Coso geothermal area, 1996-2006 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Time-dependent seismic tomography and its application to the Coso geothermal area, 1996-2006 Details Activities (1) Areas (1) Regions (0) Abstract: Measurements of temporal changes in Earth structure are commonly determined using local earthquake tomography computer programs that invert multiple seismic-wave arrival time data sets separately and assume that any differences in the structural results arise from real temporal variations. This assumption is dangerous because the results of repeated tomography experiments would differ even if the structure did not change, simply because of variation in the seismic ray distribution caused by the natural

127

Time-Dependent Seismic Tomography of the Coso Geothermal Area, 1996-2004 |  

Open Energy Info (EERE)

Dependent Seismic Tomography of the Coso Geothermal Area, 1996-2004 Dependent Seismic Tomography of the Coso Geothermal Area, 1996-2004 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Time-dependent seismic tomography of the Coso geothermal area, 1996-2004 Details Activities (1) Areas (1) Regions (0) Abstract: Local-earthquake tomographic images were calculated for each of the years 1996 - 2004 using arrival times from the U.S. Navy's permanent seismometer network at the Coso geothermal area, California. The results show irregular strengthening with time of the wave-speed ratio VP/VS at shallow depths. These changes result predominately from progressive relative increase in VS with respect to VP, and could result from processes associated with geothermal operations such as decrease in fluid pressure

128

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance  

Office of Scientific and Technical Information (OSTI)

Non-medical Uses of Computed Tomography (CT) and Nuclear Magnetic Resonance (NMR) Resources with Additional Information Computed Tomography (CT) Scanner CT Scanner - Courtesy Stanford University Department of Energy Resources Engineering Computed tomography (CT) and Nuclear Magnetic Resonance (NMR) have been used to resolve industrial problems, for materials characterizations, and to provide non-destructive evaluations for discovering flaws in parts before their use, resulting in greater reliability and greater safety for workers; to identify the presence and facilitate the recovery/extraction of oil, water, coal, and/or gas; and to provide non-destructive testing and quality control of fresh fruits and vegetables, enhancing the safety of food. These benefits of non-medical uses of CT and NMR contribute to the economy and improve people's lives.

129

Fast synchrotron X-ray tomography study of the rod packing structures  

SciTech Connect

We present a fast synchrotron X-ray tomography study of the packing structures of rods under tapping. Utilizing the high flux of the X-rays generated from the third-generation synchrotron source, we can complete a tomography scan within several seconds, after which the three-dimensional (3D) packing structure can be obtained for the subsequent structural analysis. Due to the high-energy nature of the X-ray beam, special image processing steps including image phase-retrieval has been implemented. Overall, this study suggests the possibility of acquiring statistically significant static packing structures within a reasonable time scale using high-intensity X-ray sources.

Zhang Xiaodan; Xia Chengjie; Sun Haohua; Wang Yujie [Department of Physics, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China)

2013-06-18T23:59:59.000Z

130

Simulation Study on the Characteristics of Carbon-Fiber-Reinforced Plastics in Electromagnetic Tomography Nondestructive Evaluation Systems  

Science Conference Proceedings (OSTI)

Simulations of carbon-fiber-reinforced plastics (CFRP) using the finite element method in electromagnetic tomography nondestructive evaluation systems are presented in this paper. Ansoft Maxwell 3D models describing the interaction of the sensors with ... Keywords: Carbon-fiber-reinforced plastics (CFRP), finite element, electromagnetic tomography (EMT), nondestructive evaluation (NDE), sensitivity matrix

Ze Liu; Yu Xu; Xiaofei Zhang; Yali Pei; Yiping Cheng; Wuliang Yin

2010-03-01T23:59:59.000Z

131

Adaptive-window indicator kriging: A thresholding method for computed tomography images of porous media  

Science Conference Proceedings (OSTI)

Image segmentation is a crucial step in understanding the structure of porous materials, subsequent analyses being profoundly dependent upon segmentation accuracy. Computed tomography images of naturally occurring heterogeneous materials such as soils ... Keywords: Indicator kriging, Local segmentation, Microtomography, Soil, X-ray

A. N. Houston, W. Otten, P. C. Baveye, S. Hapca

2013-04-01T23:59:59.000Z

132

Computed tomography guided localization of clinically occult breast carcinoma-the ''N'' skin guide  

SciTech Connect

Standard computed tomography (CT) can be used for the three-dimensional localization of clinically occult suspicious breast lesions whose exact position cannot be determined by standard mammographic views. A method is described that facilitates accurate preoperative needle localization using CT guidance, once the position of these lesions is defined.

Kopans, D.B.; Meyer, J.E.

1982-10-01T23:59:59.000Z

133

Open electrical impedance tomography file format: towards a first version Pascal Olivier Gaggero1  

E-Print Network (OSTI)

University, Ottawa, Canada pascal.gaggero@bfh.ch Retrieving and analyzing historical electrical impedanceOpen electrical impedance tomography file format: towards a first version Pascal Olivier Gaggero1 acquired at a different frame rate than the EIT data stream The "eit" folder stores XML

Adler, Andy

134

Lung nodule detection in low-dose and thin-slice computed tomography  

Science Conference Proceedings (OSTI)

A computer-aided detection (CAD) system for the identification of small pulmonary nodules in low-dose and thin-slice CT scans has been developed. The automated procedure for selecting the nodule candidates is mainly based on a filter enhancing spherical-shaped ... Keywords: Computer-aided detection (CAD), Image processing, Low-dose computed tomography (LDCT), Thin-slice CT

A. Retico; P. Delogu; M. E. Fantacci; I. Gori; A. Preite Martinez

2008-04-01T23:59:59.000Z

135

Analysis of hydraulic tomography using temporal moments of drawdown recovery data  

E-Print Network (OSTI)

and Tian-Chyi J. Yeh Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona are discussed subsequently. Citation: Zhu, J., and T.-C. J. Yeh (2006), Analysis of hydraulic tomography using temporal moments of drawdown recovery data, Water Resour. Res., 42, W02403, doi:10.1029/2005WR004309. 1

Daniels, Jeffrey J.

136

GPS tomography in the polar cap: comparison with ionosondes and in situ spacecraft data  

Science Conference Proceedings (OSTI)

Tomographic 4D reconstructions of ionospheric anomalies appearing in the high-latitude polar cap region are compared with plasma density measurements by digital ionosonde located near the north magnetic pole at Eureka station and with in situ plasma ... Keywords: GPS tomography, Geomagnetic storms, Ionosphere

Dimitry Pokhotelov; P. T. Jayachandran; Cathryn N. Mitchell; John W. Macdougall; Michael H. Denton

2011-01-01T23:59:59.000Z

137

Design of a DICOM image-based program for estimating patient exposure dose in computed tomography  

Science Conference Proceedings (OSTI)

During the past decade, there has been a notable worldwide increase in the number of computed tomographic (CT) examinations. Since the radiation exposure to the patient during CT examinations is relatively high, it is important to optimize the dose so ... Keywords: DICOM, computed tomography (CT), effective dose

Shuji Yamamoto; Tetsuya Horiuchi; Junko Sekiguchi; Shigeo Wada; Mitsuru Komizu; Takami Yamaguchi

2007-04-01T23:59:59.000Z

138

Time-lapse electrical resistivity tomography applied to cave sustainability (Barbados) and groundwater exploration (Saint Lucia)  

E-Print Network (OSTI)

In this work we apply the method of two-dimensional time-lapse electrical resistivity tomography (2D time-lapse ERT) for two different problems. In the first problem, we monitor the structural stability of the roof of the ...

Agramakova, Yulia

2011-01-01T23:59:59.000Z

139

Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography  

E-Print Network (OSTI)

method, Water Resources Research 36 (8), 2095-2105 Yeh, T. -determine the water saturation. However, Yeh at al. , 2000Yeh (2005), Characterization of aquifer heterogeneity using transient hydraulic tomography, Water

Brauchler, R.

2012-01-01T23:59:59.000Z

140

Simultaneous maximum-likelihood reconstruction for x-ray grating based phase-contrast tomography avoiding intermediate phase retrieval  

E-Print Network (OSTI)

Phase-wrapping artifacts, statistical image noise and the need for a minimum amount of phase steps per projection limit the practicability of x-ray grating based phase-contrast tomography, when using filtered back projection reconstruction. For conventional x-ray computed tomography, the use of statistical iterative reconstruction algorithms has successfully reduced artifacts and statistical issues. In this work, an iterative reconstruction method for grating based phase-contrast tomography is presented. The method avoids the intermediate retrieval of absorption, differential phase and dark field projections. It directly reconstructs tomographic cross sections from phase stepping projections by the use of a forward projecting imaging model and an appropriate likelihood function. The likelihood function is then maximized with an iterative algorithm. The presented method is tested with tomographic data obtained through a wave field simulation of grating based phase-contrast tomography. The reconstruction result...

Ritter, André; Durst, Jürgen; Gödel, Karl; Haas, Wilhelm; Michel, Thilo; Rieger, Jens; Weber, Thomas; Wucherer, Lukas; Anton, Gisela

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Preprocessing of backprojection images in the McClellan Nuclear Radiation Center tomography system  

DOE Green Energy (OSTI)

Neutron tomography is being investigated as a nondestructive technique for quantitative assessment of low atomic mass impurity concentration in metals. Neutrons maximize the sensitivity given their higher cross sections for low Z isotopes while tomography provides the three dimensional density information. The specific application is the detection of Hydrogen down to 200 ppm weight in aircraft engine compressor blades. A number of preprocessing corrections have been implemented for the backprojection images in order to achieve the detection requirements for a testing rate of three blades per hour. Among the procedures are corrections for neutron scattering and beam hardening. With these procedures the artifacts in tomographic reconstructions are shown to be less than the signal for 100 ppm hydrogen in titanium alloy samples.

Gibbons, M. R., LLNL

1998-02-19T23:59:59.000Z

142

Quantum process tomography and Linblad estimation of a solid state qubit  

E-Print Network (OSTI)

We present an example of quantum process tomography (QPT) performed on a single solid state qubit. The qubit used is two energy levels of the triplet state in the Nitrogen-Vacancy defect in Diamond. Quantum process tomography is applied to a qubit which has been allowed to decohere for three different time periods. In each case the process is found in terms of the chi matrix representation and the affine map representation. The discrepancy between experimentally estimated process and the closest physically valid process is noted. The results of QPT performed after three different decoherence times are used to find the error generators, or Lindblad operators, for the system, using the technique introduced by Boulant et al. [N. Boulant, T.F. Havel, M.A. Pravia and D.G. Cory, Phys. Rev. A 67, 042322 (2003)].

M. Howard; J. Twamley; C. Wittmann; T. Gaebel; F. Jelezko; J. Wrachtrup

2006-01-25T23:59:59.000Z

143

Neutron Computed Tomography of Freeze/thaw Phenomena in Polymer Electrolyte Fuel Cells  

DOE Green Energy (OSTI)

This report summarizes the final year's progress of the three-year NEER program. The overall objectives of this program were to 1) design and construct a sophisticated hight-resolution neutron computed tomography (NCT) facility, 2) develop novel and sophisticated liquid water and ice quantification analysis software for computed tomography, and 3) apply the advanced software and NCT capability to study liquid and ice distribution in polymer electrolyte fuel cells (PEFCs) under cold-start conditions. These objectives have been accomplished by the research team, enabling a new capability for advanced 3D image quantification with neutron imaging for fuel cell and other applications. The NCT water quantification methodology and software will greatly add to the capabilities of the neutron imaging community, and the quantified liquid water and ice distribution provided by its application to PEFCs will enhance understanding and guide design in the fuel cell community.

Matthew M. Mech; Jack Brenizer; Kenan Unlu; A.K. Heller

2008-12-12T23:59:59.000Z

144

Global convergence of diluted iterations in maximum-likelihood quantum tomography  

E-Print Network (OSTI)

In this paper we present an inexact stepsize selection for the Diluted R\\rho R algorithm, used to obtain the maximum likelihood estimate to the density matrix in quantum state tomography. We give a new interpretation for the diluted R\\rho R iterations that allows us to prove the global convergence under weaker assumptions. Thus, we propose a new algorithm which is globally convergent and suitable for practical implementation.

D. S. Gonçalves; M. A. Gomes-Ruggiero; C. Lavor

2013-06-13T23:59:59.000Z

145

A simple setup for neutron tomography at the Portuguese Nuclear Research Reactor  

E-Print Network (OSTI)

A simple setup for neutron radiography and tomography was recently installed at the Portuguese Research Reactor. The objective of this work was to determine the operational characteristics of the installed setup, namely the irradiation time to obtain the best dynamic range for individual images and the spatial resolution. The performance of the equipment was demonstrated by imaging a fragment of a 17th century decorative tile.

M. A. Stanojev Pereira; J. G. Marques; R. Pugliesi

2012-05-15T23:59:59.000Z

146

Simulation and preliminary performance characteristics of a computed tomography device for industrial applications  

SciTech Connect

A computed tomography system designed to function in an industrial environment is being constructed. The modular design maintains the flexibility necessary in an environment where source strength and energy, as well as detector type, could change with each application. The static nature of industrial objects also allow economies of design not possible where dynamic objects are to be analyzed. Simulation of the device has been completed and expected image qualities obtained.

Kruger, R.P.; Cannon, T.M.; Lundy, A.S.; Morris, R.A.

1978-01-01T23:59:59.000Z

147

Robust inverse scattering full waveform seismic tomography for imaging complex structure  

SciTech Connect

Seismic tomography becomes important tool recently for imaging complex subsurface. It is well known that imaging complex rich fault zone is difficult. In this paper, The application of time domain inverse scattering wave tomography to image the complex fault zone would be shown on this paper, especially an efficient time domain inverse scattering tomography and their run in cluster parallel computer which has been developed. This algorithm is purely based on scattering theory through solving Lippmann Schwienger integral by using Born's approximation. In this paper, it is shown the robustness of this algorithm especially in avoiding the inversion trapped in local minimum to reach global minimum. A large data are solved by windowing and blocking technique of memory as well as computation. Parameter of windowing computation is based on shot gather's aperture. This windowing technique reduces memory as well as computation significantly. This parallel algorithm is done by means cluster system of 120 processors from 20 nodes of AMD Phenom II. Benchmarking of this algorithm is done by means Marmoussi model which can be representative of complex rich fault area. It is shown that the proposed method can image clearly the rich fault and complex zone in Marmoussi model even though the initial model is quite far from the true model. Therefore, this method can be as one of solution to image the very complex mode.

Nurhandoko, Bagus Endar B.; Sukmana, Indriani; Wibowo, Satryo; Deny, Agus; Kurniadi, Rizal; Widowati, Sri; Mubarok, Syahrul; Susilowati; Kaswandhi [Wave Inversion and Subsurface Fluid Imaging Research (WISFIR) Lab., Complex System Research Division, Physics Department, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung. and Rock Fluid Imaging Lab., Rock Physics and Cluster C (Indonesia); Rock Fluid Imaging Lab., Rock Physics and Cluster Computing Center, Bandung (Indonesia); Physics Department of Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Rock Physics and Cluster Computing Center, Bandung, Indonesia and Institut Teknologi Telkom, Bandung (Indonesia); Rock Fluid Imaging Lab., Rock Physics and Cluster Computing Center, Bandung (Indonesia)

2012-06-20T23:59:59.000Z

148

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

149

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

150

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

151

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

152

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Wednesday, 24 February 2010 00:00 Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

153

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Imaging Antifungal Drug Molecules in Action using Soft X-Ray Tomography Print Humankind has benefitted from a long and productive relationship with yeast. For example, fermentation by yeast is an essential step in the production of bread, beer, wine, and even biofuels. However, not all yeast are beneficial. One strain of yeast, Candida albicans, grows unnoticed on most peoples' skin and in the intestines. In response to certain environmental conditions, C. albicans can switch to a pathogenic phenotype that causes infection. Yeast infections are commonplace, and in otherwise healthy individuals are usually treatable with over-the-counter medications; however, individuals with weakened immune systems can have very serious systemic consequences from a yeast infection. Treating systemic yeast infections is becoming increasingly difficult due to the growing number of yeast strains that have developed resistance to existing antimicrobial drugs. Consequently, there is a pressing need to develop new types of drugs capable of circumventing yeast drug-resistance mechanisms. To this end Stanford, University of California, San Francisco and LBNL researchers have used soft x-ray tomography to image the 3-D structure of both benign and infectious C. albicans yeast. They then imaged this yeast when treated with peptoids, a class of molecules that mimic the peptides our immune system uses as the first line of defense against microbial attack. Unlike conventional antimicrobials, microbes have yet to develop resistance mechanisms against peptides or peptoids, making them appealing candidates for pharmaceutical development.

154

New Cyclotron Targetry to Enhance F-18 clinical Position Emission Tomography  

SciTech Connect

This project proposes to develop cyclotron targets that produce F-18 for clinical Positron Emission Tomography (PET) at significantly higher rates than that available from current targetry. This production rate of 18F is directly proportional to the beam current. Higher beam currents would result in increased 18F production but would be accompanied by higher heat loads to the target. The beam power available in most commercial cyclotrons exceeds the heat removal capacity of current target technology by a factor of two to four, significantly limiting the production rate of Fluorine-18.

J. Michael Doster

2008-12-19T23:59:59.000Z

155

Minimum tomography of two entangled qutrits using local measurements of one-qutrit SIC-POVM  

E-Print Network (OSTI)

An experimental demonstration of two-qutrit state tomography via one-qutrit symmetric informationally complete positive operator-valued measure (SIC-POVM) is presented. A two-qutrit state is encoded in the transversal paths of a spontaneous parametric down-converted photon pair. A spatial light modulator allows to implement the necessary 81 POVM elements to reconstruct the state. The quality of the reconstruction is evaluated by comparing independent measurements with the predicted results calculated with the reconstructed state. Entanglement in the system is calculated via negativity and generalized robustness from the two-qutrit reconstructed density operator.

W. M. Pimenta; B. Marques; T. O. Maciel; R. O. Vianna; A. Delgado; C. Saavedra; S. Pádua

2013-12-04T23:59:59.000Z

156

Detection of foreign body using fast thermoacoustic tomography with a multielement linear transducer array  

SciTech Connect

Current imaging modalities face challenges in clinical applications due to limitations in resolution or contrast. Microwave-induced thermoacoustic imaging may provide a complementary modality for medical imaging, particularly for detecting foreign objects due to their different absorption of electromagnetic radiation at specific frequencies. A thermoacoustic tomography system with a multielement linear transducer array was developed and used to detect foreign objects in tissue. Radiography and thermoacoustic images of objects with different electromagnetic properties, including glass, sand, and iron, were compared. The authors' results demonstrate that thermoacoustic imaging has the potential to become a fast method for surgical localization of occult foreign objects.

Nie Liming; Xing Da; Yang Diwu; Zeng Lvming; Zhou Quan [MOE Key Laboratory of Laser Life Science, South China Normal University, Guangzhou 510631 (China) and Institute of Laser Life Science, South China Normal University, Guangzhou 510631 (China)

2007-04-23T23:59:59.000Z

157

Tomography of a High-Purity Narrowband Photon From a Transient Atomic Collective Excitation  

E-Print Network (OSTI)

We demonstrate the efficient heralded generation of high purity narrow-bandwidth single photons from a transient collective spin excitation in a hot atomic vapour cell. Employing optical homodyne tomography, we fully reconstruct the density matrix of the generated photon and observe a Wigner function reaching the zero value without correcting for any inefficiencies. The narrow bandwidth of the photon produced is accompanied by a high generation rate yielding a high spectral brightness. The source is therefore compatible with atomic-based quantum memories as well as other applications in light-atom interfacing. This work paves the way to preparing and measuring arbitrary superposition states of collective atomic excitations.

MacRae, A; Lvovsky, A I

2011-01-01T23:59:59.000Z

158

Three-dimensional visualization of forming Hepatitis C virus-like particles by electron-tomography  

Science Conference Proceedings (OSTI)

Hepatitis C virus infects almost 170 million people per year but its assembly pathway, architecture and the structures of its envelope proteins are poorly understood. Using electron tomography of plastic-embedded sections of insect cells, we have visualized the morphogenesis of recombinant Hepatitis C virus-like particles. Our data provide a three-dimensional sketch of viral assembly at the endoplasmic reticulum showing different budding stages and contiguity of buds. This latter phenomenon could play an important role during the assembly of wt-HCV and explain the size-heterogeneity of its particles.

Badia-Martinez, Daniel; Peralta, Bibiana [Structural Biology Unit, CIC bioGUNE, CIBERehd, 48160 Derio (Spain)] [Structural Biology Unit, CIC bioGUNE, CIBERehd, 48160 Derio (Spain); Andres, German; Guerra, Milagros [Electron Microscopy Unit, Centro de Biologia Molecular Severo Ochoa, CSIC-UAM, Campus Cantoblanco, 28049 Madrid (Spain)] [Electron Microscopy Unit, Centro de Biologia Molecular Severo Ochoa, CSIC-UAM, Campus Cantoblanco, 28049 Madrid (Spain); Gil-Carton, David [Structural Biology Unit, CIC bioGUNE, CIBERehd, 48160 Derio (Spain)] [Structural Biology Unit, CIC bioGUNE, CIBERehd, 48160 Derio (Spain); Abrescia, Nicola G.A., E-mail: nabrescia@cicbiogune.es [Structural Biology Unit, CIC bioGUNE, CIBERehd, 48160 Derio (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao (Spain)

2012-09-01T23:59:59.000Z

159

Computer-assisted tomography for the observation of oil displacement in porous media  

SciTech Connect

Computer-assisted tomography (CAT) is used to obtain cross-sectional images of Berea sandstone cores during oil displacement experiments. Local oil saturation averaged over an area of about 0.03X0.03 in. (0.8X0.8 mm) square is computed as a function of spatial position and time. A series of CAT scan images displaying the time evolution of the fluid distribution at one cross section are shown to illustrate the formation of viscous fingers.

Wang, S.Y.; Ayral, S.; Gryte, C.C.

1984-02-01T23:59:59.000Z

160

Optimization of neutron tomography for rapid hydrogen concentration inspection of metal castings  

DOE Green Energy (OSTI)

Hydrogen embrittlement describes a group of phenomena leading to the degradation of metal alloy properties. The hydrogen concentration in the alloy can be used as an indicator for the onset of embrittlement. A neutron tomography system has been optimized to perform nondestructive detection of hydrogen concentration in titanium aircraft engine compressor blades. Preprocessing of back projection images and postprocessing of tomographic reconstructions are used to achieve hydrogen concentration sensitivity below 200 ppm weight. This paper emphasizes the postprocessing techniques which allow automated reporting of hydrogen concentration.

Gibbons, M. R., LLNL

1998-02-03T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
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We encourage you to perform a real-time search of NLEBeta
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161

High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography  

DOE Patents (OSTI)

This invention permits retinal images to be acquired at high speed and with unprecedented resolution in three dimensions (4.times.4.times.6 .mu.m). The instrument achieves high lateral resolution by using adaptive optics to correct optical aberrations of the human eye in real time. High axial resolution and high speed are made possible by the use of Fourier-domain optical coherence tomography. Using this system, we have demonstrated the ability to image microscopic blood vessels and the cone photoreceptor mosaic.

Olivier, Scot S. (Livermore, CA); Werner, John S. (Davis, CA); Zawadzki, Robert J. (Sacramento, CA); Laut, Sophie P. (Pasedena, CA); Jones, Steven M. (Livermore, CA)

2010-09-07T23:59:59.000Z

162

Implementation of sub-nanoseconds TDC in FPGA: applications to time-of-flight analysis in muon radiography  

E-Print Network (OSTI)

Time-of-flight (tof) techniques are standard techniques in high energy physics to determine particles propagation directions. Since particles velocities are generally close to c, the speed of light, and detectors typical dimensions at the meter level, the state-of-the-art tof techniques should reach sub-nanosecond timing resolution. Among the various techniques already available, the recently developed ring oscillator TDC ones, implemented in low cost FPGA, feature a very interesting figure of merit since a very good timing performance may be achieved with limited processing ressources. This issue is relevant for applications where unmanned sensors should have the lowest possible power consumption. Actually this article describes in details the application of this kind of tof technique to muon tomography of geological bodies. Muon tomography aims at measuring density variations and absolute densities through the detection of atmospheric muons flux's attenuation, due to the presence of matter. When the measure...

Marteau, J; Gibert, D; Jourde, K; Gardien, S; Girerd, C; Ianigro, J -C

2013-01-01T23:59:59.000Z

163

High Quality Image of Biomedical Object by X-ray Refraction Based Contrast Computed Tomography  

SciTech Connect

Recently we have developed a new Computed Tomography (CT) algorithm for refraction contrast that uses the optics of diffraction-enhanced imaging. We applied this new method to visualize soft tissue which is not visualized by the current absorption based contrast. The meaning of the contrast that appears in refraction-contrast X-ray CT images must be clarified from a biologic or anatomic point of view. It has been reported that the contrast is made with the specific gravity map with a range of approximately 10 {mu}arc sec. However, the relationship between the contrast and biologic or anatomic findings has not been investigated, to our knowledge. We compared refraction-contrast X-ray CT images with microscopic X-ray images, and we evaluated refractive indexes of pathologic lesions on phase-contrast X-ray CT images. We focused our attenuation of breast cancer and lung cancer as samples. X-ray refraction based Computed Tomography was appeared to be a pathological ability to depict the boundary between cancer nest and normal tissue, and inner structure of the disease.

Hashimoto, E. [Department of Photon-Science, School of Advanced Studies, Graduate University for Advanced Studies (GUAS), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Maksimenko, A.; Hirano, K.; Hyodo, K. [Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Sugiyama, H. [Department of Photon-Science, School of Advanced Studies, Graduate University for Advanced Studies (GUAS), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Shimao, D. [Department of Health Sciences, Ibaraki prefectural University of Health Sciences, 4669-2Ami, Ami, Inashiki, Ibaraki, 300-0394 (Japan); Nishino, Y.; Ishikawa, T. [RIKEN Harima Institute, 1-1-1 Kouto, Mikazuki, Sayo, Hyogo, 679-5148 (Japan); Yuasa, T. [Department of Bio-system Engineering, Faculty of Engineering Yamagata University, 4-3-16 Jonan, Yonezawa, Yamagata 992-8510 (Japan); Ichihara, S. [Dept. of Path., Nagoya Med. Center, Nat. Hospital Organization, Naka-ku, Nagoya 460-0001 (Japan); Arai, Y. [Matsumoto Dental University, 1980 Hirooka, Shiojiri, Nagano (Japan); Ando, M. [Department of Photon-Science, School of Advanced Studies, Graduate University for Advanced Studies (GUAS), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Inst. of Sci. and Tech., Tokyo Univ. of Science, Yamasaki 2641, Noda, Chiba 278-8510 (Japan)

2007-01-19T23:59:59.000Z

164

Using seismic tomography to characterize fracture systems induced by hydraulic fracturing  

DOE Green Energy (OSTI)

Microearthquakes induced by hydraulic fracturing have been studied by many investigators to characterize fracture systems created by the fracturing process and to better understand the locations of energy resources in the earth`s subsurface. The pattern of the locations often contains a great deal of information about the fracture system stimulated during the hydraulic fracturing. Seismic tomography has found applications in many areas for characterizing the subsurface of the earth. It is well known that fractures in rock influence both the P and S velocities of the rock. The influence of the fractures is a function of the geometry of the fractures, the apertures and number of fractures, and the presence of fluids in the fractures. In addition, the temporal evolution of the created fracture system can be inferred from the temporal changes in seismic velocity and the pattern of microearthquake locations. Seismic tomography has been used to infer the spatial location of a fracture system in a reservoir that was created by hydraulic fracturing.

Fehler, M.; Rutledge, J.

1995-01-01T23:59:59.000Z

165

Radiation-induced lung injury using a pig model: Evaluation by high-resolution computed tomography  

Science Conference Proceedings (OSTI)

To assess the early phase of radiation-induced lung injury using high-resolution computed tomography (CT) under experimental conditions and to perform precise CT-pathologic correlation. Five Yorkshire pigs received a single dose of 12.5 Gy to the right lower lung. Computed tomographic images were obtained at 2-week intervals. The animals were killed after follow-up periods of 4-16 weeks. The lungs were removed, inflated, fixed, dried, and sliced corresponding to the CT sections. Computed tomography, specimen radiography, and histologic findings were correlated. Various CT findings were observed during the first 16 weeks, including ground-glass opacity, discrete consolidation, patchy consolidation, thickened interlobular septum, and bronchovascular bundle. Ground-glass opacity was associated with thickened alveolar wall and scattered tiny fibrotic foci. Thickened interlobular septum and bronchovascular bundle were the results of fibrosis adjacent to these structures. Discrete consolidation correlated with intraalveolar edema with hemorrhage and infiltration of inflammatory cells. High-resolution CT correlated well with pathology of the lung due to radiation injury as verified by precise radiologic-pathologic correlation. 28 refs., 4 figs., 1 tab.

Takahashi, Masashi; Balazs, G.; Moskowitz, G.W.; Palestro, C.J.; Eacobacci, T.; Khan, A.; Herman, P.G. [Albert Einstein College of Medicine, New Hyde Park, NY (United States)

1995-02-01T23:59:59.000Z

166

Three-dimensional characterization of near-field transducers by electron tomography  

SciTech Connect

Transmission electron microscopy (TEM) was employed to study the structure of near-field transducers (NFT) for applications in heat-assisted magnetic recording (HAMR) heads. The overall shape of NFTs that had passed or failed an optical test was similar, as determined by scanning transmission electron microscopy tomography. However, the absence of a well-defined peg and the presence of a flat top on the 'FAIL' NFT disk induced poor thermal heat transfer from the NFT to the phase change medium and resulted in the optical test failure. The thermal heating around the NFT led to Ta diffusion from the adjacent tantala core and to the presence of Ta-rich particles in the alumina matrix in the plane of the NFT. - Highlights: Black-Right-Pointing-Pointer Very site specific TEM specimen prepared by dual-beam SEM/FIB system. Black-Right-Pointing-Pointer Near field transducer characterization by STEM tomography. Black-Right-Pointing-Pointer Elemental analysis in 2D by STEM-EDX.

Liu, Yuzi, E-mail: yuziliu@anl.gov [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States) [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Center for Nanoscale Materials, Argonne National Laboratory, Argonne IL, 60439 (United States); Schreiber, Daniel K. [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States) [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208 (United States); Petford-Long, Amanda K. [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States) [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Center for Nanoscale Materials, Argonne National Laboratory, Argonne IL, 60439 (United States); Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208 (United States); Gao, Kai-Zhong [Head and Media R and D, Seagate Technology, Bloomington, MN 55435 (United States)] [Head and Media R and D, Seagate Technology, Bloomington, MN 55435 (United States)

2012-10-15T23:59:59.000Z

167

Enhanced x-ray imaging for a thin film cochlear implant with metal artefacts using phase retrieval tomography  

SciTech Connect

Phase retrieval tomography has been successfully used to enhance imaging in systems that exhibit poor absorption contrast. However, when highly absorbing regions are present in a sample, so-called metal artefacts can appear in the tomographic reconstruction. We demonstrate that straightforward approaches for metal artefact reconstruction, developed in absorption contrast tomography, can be applied when using phase retrieval. Using a prototype thin film cochlear implant that has high and low absorption components made from iridium (or platinum) and plastic, respectively, we show that segmentation of the various components is possible and hence measurement of the electrode geometry and relative location to other regions of interest can be achieved.

Arhatari, B. D. [Department of Physics, La Trobe University, Victoria 3086 (Australia); ARC Centre of Excellence for Coherent X-ray Science, Melbourne (Australia); Harris, A. R.; Paolini, A. G. [School of Psychological Science, La Trobe University, Victoria 3086 (Australia); ARC Centre of Excellence for Electromaterials Science, Melbourne (Australia); Peele, A. G. [Department of Physics, La Trobe University, Victoria 3086 (Australia); ARC Centre of Excellence for Coherent X-ray Science, Melbourne (Australia); Australian Synchrotron, Victoria 3168 (Australia)

2012-06-01T23:59:59.000Z

168

Electron holographic tomography for mapping the three-dimensional distribution of electrostatic potential in III-V semiconductor nanowires  

Science Conference Proceedings (OSTI)

Electron holographic tomography (EHT), the combination of off-axis electron holography with electron tomography, is a technique, which can be applied to the quantitative 3-dimensional (3D) mapping of electrostatic potential at the nanoscale. Here, we show the results obtained in the EHT investigation of GaAs and GaAs-AlGaAs core-shell nanowires grown by Au-catalysed metalorganic vapor phase epitaxy. The unique ability of EHT of disentangling the materials mean inner potential (MIP) from the specimen projected thickness allows reconstruction of the nanowire 3D morphology and inner compositional structure as well as the measurement of the MIP.

Wolf, D.; Lichte, H. [Triebenberg Laboratory, Institute of Structure Physics, Technische Universitaet Dresden, D-01062 Dresden (Germany); Pozzi, G. [Department of Physics, Universita di Bologna, Viale B. Pichat 6/2, I-40127 Bologna (Italy); Prete, P. [IMM-CNR, Lecce Research Unit, S.P. 6 Lecce-Monteroni, I-73100 Lecce (Italy); Lovergine, N. [Dipartimento di Ingegneria dell'Innovazione, Universita del Salento, S.P. 6 Lecce-Monteroni, I-73100 Lecce (Italy)

2011-06-27T23:59:59.000Z

169

3-D Electrical Resistivity Tomography for Cliff Stability Assessment at Pointe du Hoc in Normandy, France  

E-Print Network (OSTI)

Pointe du Hoc overlooking the English Channel in Normandy, France was host to one of the most important military engagements of World War II. While the site is a valuable historic cultural resource, it is vulnerable to cliff collapses that already have endangered the observation post and Rudder?s command post. The observation post has been closed to visitors for some time due to safety concerns. Geophysical techniques have been used increasingly in recent years for slope stability investigation purposes. The objective of this study is to apply advanced 3?D resistivity tomography toward a detailed site stability assessment with special attention to the two at-risk buildings. 3?D resistivity tomography datasets at Pointe du Hoc in the presence of extreme topography and dense cultural clutter have been successfully acquired, inverted, and interpreted. The cliff stability in the areas around the two at?risk buildings has been analyzed. A hazard assessment scheme has been designed in which regions of high resistivity are interpreted as zones of open, dry fractures with a moderate mass movement potential. Regions of low resistivity are zones of wet, clay?filled fractures with a high mass movement potential. The observation post tomography results indicate that the highest mass movement hazard appears to be associated with the marine caverns at the base of the cliff that are positioned at the point of strongest wave attack. These caverns likely occupy the future site of development of a sea arch which will definitely threaten the observation post building. A high probability of a soil wedge failure is on the east?facing cliff edge close to the observation post that could damage or destroy the building. The mass movement potential at the Rudder?s command post area is low to moderate. The greatest risk is associated with soil wedge failures at the top of the cliffs. The resistivity geophysical data add great value to the natural geohazard assessment at Pointe du Hoc and constitute an integral component of an interdisciplinary approach to the problem of cultural resource preservation at the site. Geophysics is a non?invasive and relatively inexpensive technology that provides unique constraints which are unobtainable using traditional engineering geology methods for site characterization. However, the technology is difficult to master and the inherent limitations must be carefully understood to ensure a reliable geotechnical interpretation.

Udphuay, Suwimon

2008-12-01T23:59:59.000Z

170

Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography  

SciTech Connect

In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

2012-01-10T23:59:59.000Z

171

arXiv:astro-ph/0208093v327Nov2002 Dark Energy and Matter Evolution from Lensing Tomography  

E-Print Network (OSTI)

arXiv:astro-ph/0208093v327Nov2002 Dark Energy and Matter Evolution from Lensing Tomography Wayne Hu on the growth function of structure and the evolution of the dark energy density. We examine this potential tests for the existence of multiple dark matter components or a dark energy component

Hu, Wayne

172

Storage of Pressuirzed Carbon Dioxide in Coal Observed Using X-Ray Tomography  

NLE Websites -- All DOE Office Websites (Extended Search)

OF PRESSURIZED CARBON DIOXIDE IN COAL OBSERVED USING X-RAY OF PRESSURIZED CARBON DIOXIDE IN COAL OBSERVED USING X-RAY TOMOGRAPHY Jonathan P. Mathews (jpm10@psu.edu; 814 863 6213) Ozgen Karacan, (karacan@pnge.psu.edu; 814 865 9570) Phillip Halleck (phil@pnge.psu.edu; 814 863 1701) Gareth D. Mitchell (n8h@psu.edu; 814 863 6543) Abraham Grader (grader@pnge.psu.edu; 814 863 5813) The Energy Institute & Department of Energy & GeoEnvironmental Engineering 151 Holser Building, The Pennsylvania State University University Park, PA 16802 Introduction The sequestration of CO 2 in coal seams has been proposed as a mitigation strategy for climate change. To maximize sorption potential it is essential that the heterogeneity of the coal seam be represented in the computational models used to predict the complex flow and sorption within

173

Pre- and post-selected quantum states: density matrices, tomography, and Kraus operators  

E-Print Network (OSTI)

We present a general formalism for charecterizing 2-time quantum states, describing pre- and post-selected quantum systems. The most general 2-time state is characterized by a `density vector' that is independent of measurements performed between the preparation and post-selection. We provide a method for performing tomography of an unknown 2-time density vector. This procedure, which cannot be implemented by weak or projective measurements, brings new insight to the fundamental role played by Kraus operators in quantum measurements. Finally, after showing that general states and measurements are isomorphic, we show that any measurement on a 2-time state can be mapped to a measurement on a preselected bipartite state.

Ralph Silva; Yelena Guryanova; Nicolas Brunner; Noah Linden; Anthony J. Short; Sandu Popescu

2013-08-09T23:59:59.000Z

174

Demonstration of Emitted-Neutron Computed Tomography to Quantify Nuclear Materials  

Science Conference Proceedings (OSTI)

In this document, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM). The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable essentially pure fast-neutron imaging. The system is capable of high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolves neutron sources similar in dimension to a fuel pellet, or about 1 cm. During measurements of Pu MOX fuel rodlet arrays in soup cans at the INL ZPPR facility, the position of a partial defect of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected.

Hausladen, Paul [ORNL; Blackston, Matthew A [ORNL; Newby, Robert Jason [ORNL

2011-09-01T23:59:59.000Z

175

Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): Sensitivity Studies  

NLE Websites -- All DOE Office Websites (Extended Search)

Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): Sensitivity Studies Robin L. Newmark (newmark@llnl.gov, 925-423-3644) Abelardo L. Ramirez (ramirez3@llnl.gov; 925-422-6909) William D. Daily (daily1@llnl.gov; 925-422-8623) Lawrence Livermore National Laboratory P.O. Box 808 Livermore, Ca. 94550 Abstract If geologic formations are used to sequester carbon dioxide (CO 2 ), monitoring the CO 2 injection will be required to confirm the performance of the reservoir system, assess leaks and flow paths, and understand the geophysical and geochemical interactions between the CO 2 and the geologic minerals and fluids. Electrical methods are well suited for monitoring processes involving fluids, as electrical properties are sensitive to the

176

Time-dependent seismic tomography of the Coso geothermal area, 1996-2004 |  

Open Energy Info (EERE)

of the Coso geothermal area, 1996-2004 of the Coso geothermal area, 1996-2004 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Time-dependent seismic tomography of the Coso geothermal area, 1996-2004 Details Activities (1) Areas (1) Regions (0) Abstract: Local-earthquake tomographic images were calculated for each of the years 1996 - 2004 using arrival times from the U.S. Navy's permanent seismometer network at the Coso geothermal area, California. The results show irregular strengthening with time of the wave-speed ratio VP/VS at shallow depths. These changes result predominately from progressive relative increase in VS with respect to VP, and could result from processes associated with geothermal operations such as decrease in fluid pressure and the drying of argillaceous minerals such as illite.

177

Coherent exciton dynamics in supramolecular light-harvesting nanotubes revealed by ultrafast quantum process tomography  

E-Print Network (OSTI)

Long-lived exciton coherences have been recently observed in photosynthetic complexes via ultrafast spectroscopy, opening exciting possibilities for the study and design of coherent exciton transport. Yet, ambiguity in the spectroscopic signals has led to arguments for interpreting them in terms of the exciton dynamics, demanding more stringent tests. We propose a novel strategy, Quantum Process Tomography (QPT) for ultrafast spectroscopy, to reconstruct the evolving quantum state of excitons in double-walled supramolecular light-harvesting nanotubes at room temperature. The protocol calls for eight transient grating experiments with varied pulse spectra. Our analysis reveals unidirectional energy transfer from the outer to the inner wall excitons, absence of nonsecular processes, and an unexpected coherence between those two states lasting about 150 femtoseconds, indicating weak electronic coupling between the walls. Our work constitutes the first experimental QPT in a 'warm' and complex system, and provides an elegant scheme to maximize information from ultrafast spectroscopy experiments.

Joel Yuen-Zhou; Dylan H. Arias; Dorthe M. Eisele; Colby P. Steiner; Jacob J. Krich; Moungi Bawendi; Keith A. Nelson; Alán Aspuru-Guzik

2013-08-19T23:59:59.000Z

178

Atomic Scale Characterization of Compound Semiconductors using Atom Probe Tomography: Preprint  

DOE Green Energy (OSTI)

Internal interfaces are critical in determining the performance of III-V multijunction solar cells. Studying these interfaces with atomic resolution using a combination of transmission electron microscopy (TEM), atom probe tomography (APT), and density functional calculations enables a more fundamental understanding of carrier dynamics in photovoltaic (PV) device structures. To achieve full atomic scale spatial and chemical resolution, data acquisition parameters in laser pulsed APT must be carefully studied to eliminate surface diffusion. Atom probe data with minimized group V ion clustering and expected stoichiometry can be achieved by adjusting laser pulse power, pulse repetition rate, and specimen preparation parameters such that heat flow away from the evaporating surface is maximized. Applying these improved analysis conditions to III-V based PV gives an atomic scale understanding of compositional and dopant profiles across interfaces and tunnel junctions and the initial stages of alloy clustering and dopant accumulation. Details on APT experimental methods and future in-situ instrumentation developments are illustrated.

Gorman, B. P.; Guthrey, H.; Norman, A. G.; Al-Jassim, M.; Lawrence, D.; Prosa, T.

2011-07-01T23:59:59.000Z

179

Carbon nanotube based microfocus field emission x-ray source for microcomputed tomography  

Science Conference Proceedings (OSTI)

Microcomputed tomography is now widely used for in vivo small animal imaging for cancer studies. Achieving high imaging quality of live objects requires the x-ray source to have both high spatial and temporal resolutions. Preliminary studies have shown that carbon nanotube (CNT) based field emission x-ray source has significant intrinsic advantages over the conventional thermionic x-ray tube including better temporal resolution and programmability. Here we report the design and characterization of a CNT based field emission x-ray source that also affords a high spatial resolution. The device uses modified asymmetric Einzel lenses for electron focusing and an elliptical shaped CNT cathode patterned by photolithography. Stable and small isotropic x-ray focal spot sizes were obtained.

Liu Zejian; Yang Guang; Lee, Yueh Z.; Bordelon, David; Lu Jianping; Zhou, Otto [Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); School of Medicine, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27599 and Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

2006-09-04T23:59:59.000Z

180

Constructing Anatomically Accurate Face Models using Computed Tomography and Cyberware data  

E-Print Network (OSTI)

Facial animation and cranio-facial surgery simulation both stand to benefit from the development of anatomically accurate computer models of the human face. State-of-theart biomechanical models of the face have shown promise in animation, but they are inadequate for the purposes of cranio-facial surgery simulation. The goal of this thesis is to develop an improved facial model, using Cyberware data which captures the external structure and appearance of the face and head, as well as computed tomography (CT) data which captures the internal structure of facial soft and hard tissues. To this end, we develop algorithms to (1) register the CT and Cyberware datasets, (2) extract from the CT data a skull subsurface which serves as a foundation of the soft-tissue model, and (3) compute thic...

Faisal Zubair Qureshi

2000-01-01T23:59:59.000Z

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181

Semiconductor detectors for medical tomography with high-energy heavy ions  

SciTech Connect

High-energy heavy ion beams are in use at the Lawrence Berkeley Laboratory for cancer therapy. In order to take full advantage of the very favorable depth-dose characteristics of those beams, it is necessary to determine the stopping characteristics of the ions in the complex media of a human with greater accuracy than obtainable with x-ray CAT scanning. Initial measurements with an array of Si dE/dx position sensitive detectors and a windowless thin planar Ge detector used in a side entry mode show the potential for fabricating an instrument for high accuracy on-line CAT scanning using the same ions to be used for therapy. It is estimated that one tomography can be obtained with a dose of 0.72 Rad-gm.

Llacer, J.; Haller, E.E.; Hansen, W.L.; Walton, J.T.; Batho, E.K.

1980-11-01T23:59:59.000Z

182

Comparison of radionuclide scans with computer-assisted tomography in diagnosis of intracranial disease  

SciTech Connect

Radionuclide brain scans were compared with computer-assisted tomography (CAT) for the diagnosis of intracranial disorders in 297 patients. The diagnosis was confirmed in 281 patients who formed the population for the study. The radionuclide scan was false positive for 12 patients (3.9 percent) and false negative for eight (2.6 percent). The CAT was false positive for three patients (1 percent) and false negative for one (0.3 percent). In the 133 patients in whom both tests were negative, no evidence of central nervous system pathology has been found during the 6 to 18 month follow-up. Brain tumors and intracerebral hemorrhage are more readily detectable with CAT.

Clifford, J.R.; Connolly, E.S.; Voorhies, R.M.

1976-12-01T23:59:59.000Z

183

Computed axial tomography (CAT) contribution for dosimetry and treatment evaluation in lung cancer  

SciTech Connect

The use of computed axial tomography (CAT) scans in postoperative patients with lung cancer was studied to evaluate its contribution in dosimetry and to study the late effects of irradiation. Comparisons were made between the treatment planning generated from CAT scan data and that obtained from two orthogonal radiographs. Both methods offered a good approximation but with orthogonal radiographs possible mediastinal and lung shift could not be seen and the dose delivered to the spinal cord was overestimated. A control CAT scan performed 6 to 18 months after treatment showed a lung fibrosis that was strictly correlated with the treatment planning and related with doses and volume treated. CAT scans allowed more accurate treatment planning.

Van Houtte, P.; Piron, A.; Lustman-Marechal, J.; Osteaux, M.; Henry, J.

1980-08-01T23:59:59.000Z

184

Investigation of plasma-doped fin structure and characterization of dopants by atom probe tomography  

Science Conference Proceedings (OSTI)

As and P dopants in a plasma-doped Si-based fin structure were analyzed using atom probe tomography. The distributions and concentrations of As and P atoms in various regions of the fin structure and the oxidation levels for different dopants were determined. Most dopants were segregated at the fin boundary, and the As and P concentrations exceeded 9 Multiplication-Sign 10{sup 20} atoms/cm{sup 3} and 2 Multiplication-Sign 10{sup 20} atoms/cm{sup 3}, respectively. The atomic oxygen and SiO{sub 2} concentrations depended on the dopant type. The larger and heavier As dopant severely damaged the surface of the fin structure and could cause more severe oxidation.

Kim, B. H.; Park, S. M. [Department of Materials Science and Engineering, POSTECH, Pohang (Korea, Republic of); Park, S. W.; Park, Y. B.; Kim, H. J. [Research and Development Division, SK Hynix, 2091, Gyeongchung-daero, Bubal-eub, Ichon-si, Gyeonggi-do (Korea, Republic of); Park, C. G. [Department of Materials Science and Engineering, POSTECH, Pohang (Korea, Republic of); National Center for Nanomaterials Technology (NCNT), Pohang 790-784 (Korea, Republic of)

2012-11-19T23:59:59.000Z

185

Computing traveltime and amplitude sensitivity kernels in finite-frequency tomography  

Science Conference Proceedings (OSTI)

The efficient computation of finite-frequency traveltime and amplitude sensitivity kernels for velocity and attenuation perturbations in global seismic tomography poses problems both of numerical precision and of validity of the paraxial approximation used. We investigate these aspects, using a local model parameterization in the form of a tetrahedral grid with linear interpolation in between grid nodes. The matrix coefficients of the linear inverse problem involve a volume integral of the product of the finite-frequency kernel with the basis functions that represent the linear interpolation. We use local and global tests as well as analytical expressions to test the numerical precision of the frequency and spatial quadrature. There is a trade-off between narrowing the bandpass filter and quadrature accuracy and efficiency. Using a minimum step size of 10 km for S waves and 30 km for SS waves, relative errors in the quadrature are of the order of 1% for direct waves such as S, and a few percent for SS waves, which are below data uncertainties in delay time or amplitude anomaly observations in global seismology. Larger errors may occur wherever the sensitivity extends over a large volume and the paraxial approximation breaks down at large distance from the ray. This is especially noticeable for minimax phases such as SS waves with periods >20 s, when kernels become hyperbolic near the reflection point and appreciable sensitivity extends over thousands of km. Errors becomes intolerable at epicentral distance near the antipode when sensitivity extends over all azimuths in the mantle. Effects of such errors may become noticeable at epicentral distances > 140{sup o}. We conclude that the paraxial approximation offers an efficient method for computing the matrix system for finite-frequency inversions in global tomography, though care should be taken near reflection points, and alternative methods are needed to compute sensitivity near the antipode.

Tian Yue [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)], E-mail: ytian@princeton.edu; Montelli, Raffaella [ExxonMobil Upstream Research Company, P.O. Box 22189, GW03-940A, Houston, TX 77252-2189 (United States); Nolet, Guust; Dahlen, F.A. [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)

2007-10-01T23:59:59.000Z

186

Markov Random Field Based Automatic Image Alignment for ElectronTomography  

SciTech Connect

Cryo electron tomography (cryo-ET) is the primary method for obtaining 3D reconstructions of intact bacteria, viruses, and complex molecular machines ([7],[2]). It first flash freezes a specimen in a thin layer of ice, and then rotates the ice sheet in a transmission electron microscope (TEM) recording images of different projections through the sample. The resulting images are aligned and then back projected to form the desired 3-D model. The typical resolution of biological electron microscope is on the order of 1 nm per pixel which means that small imprecision in the microscope's stage or lenses can cause large alignment errors. To enable a high precision alignment, biologists add a small number of spherical gold beads to the sample before it is frozen. These beads generate high contrast dots in the image that can be tracked across projections. Each gold bead can be seen as a marker with a fixed location in 3D, which provides the reference points to bring all the images to a common frame as in the classical structure from motion problem. A high accuracy alignment is critical to obtain a high resolution tomogram (usually on the order of 5-15nm resolution). While some methods try to automate the task of tracking markers and aligning the images ([8],[4]), they require user intervention if the SNR of the image becomes too low. Unfortunately, cryogenic electron tomography (or cryo-ET) often has poor SNR, since the samples are relatively thick (for TEM) and the restricted electron dose usually results in projections with SNR under 0 dB. This paper shows that formulating this problem as a most-likely estimation task yields an approach that is able to automatically align with high precision cryo-ET datasets using inference in graphical models. This approach has been packaged into a publicly available software called RAPTOR-Robust Alignment and Projection estimation for Tomographic Reconstruction.

Moussavi, Farshid; Amat, Fernando; Comolli, Luis R.; Elidan, Gal; Downing, Kenneth H.; Horowitz, Mark

2007-11-30T23:59:59.000Z

187

Impact of computed tomography and {sup 18}F-deoxyglucose coincidence detection emission tomography image fusion for optimization of conformal radiotherapy in non-small-cell lung cancer  

SciTech Connect

Purpose: To report a retrospective study concerning the impact of fused {sup 18}F-fluoro-deoxy-D-glucose (FDG)-hybrid positron emission tomography (PET) and CT images on three-dimensional conformal radiotherapy planning for patients with non-small-cell lung cancer. Methods and Materials: A total of 101 patients consecutively treated for Stage I-III non-small-cell lung cancer were studied. Each patient underwent CT and FDG-hybrid PET for simulation treatment in the same treatment position. Images were coregistered using five fiducial markers. Target volume delineation was initially performed on the CT images, and the corresponding FDG-PET data were subsequently used as an overlay to the CT data to define the target volume. Results: {sup 18}F-fluoro-deoxy-D-glucose-PET identified previously undetected distant metastatic disease in 8 patients, making them ineligible for curative conformal radiotherapy (1 patient presented with some positive uptake corresponding to concomitant pulmonary tuberculosis). Another patient was ineligible for curative treatment because the fused PET-CT images demonstrated excessively extensive intrathoracic disease. The gross tumor volume (GTV) was decreased by CT-PET image fusion in 21 patients (23%) and was increased in 24 patients (26%). The GTV reduction was {>=}25% in 7 patients because CT-PET image fusion reduced the pulmonary GTV in 6 patients (3 patients with atelectasis) and the mediastinal nodal GTV in 1 patient. The GTV increase was {>=}25% in 14 patients owing to an increase in the pulmonary GTV in 11 patients (4 patients with atelectasis) and detection of occult mediastinal lymph node involvement in 3 patients. Of 81 patients receiving a total dose of {>=}60 Gy at the International Commission on Radiation Units and Measurements point, after CT-PET image fusion, the percentage of total lung volume receiving >20 Gy increased in 15 cases and decreased in 22. The percentage of total heart volume receiving >36 Gy increased in 8 patients and decreased in 14. The spinal cord volume receiving at least 45 Gy (2 patients) decreased. Multivariate analysis showed that tumor with atelectasis was the single independent factor that resulted in a significant effect on the modification of the size of the GTV by FDG-PET: tumor with atelectasis (with vs. without atelectasis, p = 0.0001). Conclusion: The results of our study have confirmed that integrated hybrid PET/CT in the treatment position and coregistered images have an impact on treatment planning and management of non-small-cell lung cancer. However, FDG images using dedicated PET scanners and respiration-gated acquisition protocols could improve the PET-CT image coregistration. Furthermore, the impact on treatment outcome remains to be demonstrated.

Deniaud-Alexandre, Elisabeth [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); Touboul, Emmanuel [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France)]. E-mail: emmanuel.touboul@tnn.aphp.fr; Lerouge, Delphine [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); Grahek, Dany [Department of Nuclear Medicine, Tenon Hospital A.P.-H.P., Paris (France); Foulquier, Jean-Noel [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); Petegnief, Yolande [Department of Nuclear Medicine, Tenon Hospital A.P.-H.P., Paris (France); Gres, Benoit [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); El Balaa, Hanna [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); Keraudy, Katia [Department of Radiation Oncology, Tenon Hospital A.P.-H.P., Paris (France); Kerrou, Kaldoun [Department of Nuclear Medicine, Tenon Hospital A.P.-H.P., Paris (France); Montravers, Francoise [Department of Nuclear Medicine, Tenon Hospital A.P.-H.P., Paris (France); Milleron, Bernard [Department of Respiratory Medicine, Tenon Hospital A.P.-H.P., Paris (France); Lebeau, Bernard [Department of Respiratory Medicine, Saint-Antoine Hospital A.P.-H.P., Paris (France) and Cancerest, Paris VI University, Paris (France); Talbot, Jean-Noel [Department of Nuclear Medicine, Tenon Hospital A.P.-H.P., Paris (France)

2005-12-01T23:59:59.000Z

188

Addressing the risks of diagnostic radiology : what should be done about the increasing use of computed tomography in the United States  

E-Print Network (OSTI)

Computed tomography (CT) is a prominent procedure in the US with larger radiation doses than traditional radiology. CT is a powerful tool in the diagnosis of a wide variety of conditions and its use has grown quickly because ...

Eastwick, Gary (Gary A.)

2010-01-01T23:59:59.000Z

189

Acoustic Tomography as a Remote Sensing Method to Investigate the Near-Surface Atmospheric Boundary Layer in Comparison with In Situ Measurements  

Science Conference Proceedings (OSTI)

The acoustic tomography method is applied in the atmospheric surface layer to observe near-surface temperature fields. Important advantages of this technique are the remote sensing capacity and the possibility of directly deriving area-average ...

Astrid Ziemann; Klaus Arnold; Armin Raabe

2002-08-01T23:59:59.000Z

190

High-speed digitization readout of silicon photomultipliers for time of flight positron emission tomography  

Science Conference Proceedings (OSTI)

We report on work to develop a system with about 100 picoseconds (ps) time resolution for time of flight positron emission tomography [TOF-PET]. The chosen photo detectors for the study were Silicon Photomultipliers (SiPM's). This study was based on extensive experience in studying timing properties of SiPM's. The readout of these devices used the commercial high speed digitizer DRS4. We applied different algorithms to get the best time resolution of 155 ps Guassian (sigma) for a LYSO crystal coupled to a SiPM. We consider the work as a first step in building a prototype TOF-PET module. The field of positron-emission-tomography (PET) has been rapidly developing. But there are significant limitations in how well current PET scanners can reconstruct images, related to how fast data can be acquired, how much volume they can image, and the spatial and temporal resolution of the generated photons. Typical modern scanners now include multiple rings of detectors, which can image a large volume of the patient. In this type of scanner, one can treat each ring as a separate detector and require coincidences only within the ring, or treat the entire region viewed by the scanner as a single 3 dimensional volume. This 3d technique has significantly better sensitivity since more photon pair trajectories are accepted. However, the scattering of photons within the volume of the patient, and the effect of random coincidences limits the technique. The advent of sub-nanosecond timing resolution detectors means that there is potentially much better rejection of scattered photon events and random coincidence events in the 3D technique. In addition, if the timing is good enough, then the origin of photons pairs can be determined better, resulting in improved spatial resolution - so called 'Time-of-Flight' PET, or TOF-PET. Currently a lot of activity has occurred in applications of SiPMs for TOF-PET. This is due to the devices very good time resolution, low profile, lack of high voltage needed, and their non-sensitivity to magnetic fields. While investigations into this technique have begun elsewhere, we feel that the extensive SiPM characterization and data acquisition expertise of Fermilab, and the historical in-depth research of PET imaging at University of Chicago will combine to make significant strides in this field. We also benefit by a working relationship with the SiPM producer STMicroelectronics (STM).

Ronzhin, A.; Los, S.; Martens, M.; Ramberg, E.; /Fermilab; Kim, H.; Chen, C.; Kao, C.; /Chicago U.; Niessen, K.; /SUNY, Buffalo; Zatserklyaniy, A.; /Puerto Rico U., Mayaguez; Mazzillo, M.; Carbone, B.; /SGS Thomson, Catania

2011-02-01T23:59:59.000Z

191

Cranial computed tomography and real-time sonography in full-term neonates and infants  

Science Conference Proceedings (OSTI)

The results of cranial ultrasonography (US) and computed tomography (CT) were compared in 52 full-term neonates and young infants. The chief indications for examination included: increasing head size, dysmorphic features, myelomeningocele, inflammatory disease, and asphyxia. Disorders detected included hydrocephalus, parenchymal abnormalities, intracranial hemorrhage, extraparenchymal fluid collections, and vascular and other developmental malformations. CT and US essentially were equivalent in detecting hydrocephalus, moderate to large intraventricular hemorrhages or subdural collections, and large focal parenchymal lesions, although CT was somewhat better in determining the level and cause of obstruction in patients with hydrocephalus and characterizing parenchymal abnormalities. CT was more sensitive than ultrasound in detecting subarachnoid hemorrhage (100% vs. 0%), diffuse parenchymal abnormality (100% vs. 33%), and small intraventricular hemorrhages (100% vs. 0%) but these lesions often were not clinically significant. The results suggest that US should be used as the primary neuroradiological examination in term infants; CT probably should be reserved for further investigation after US in those patients with a history of hypoxia and progressive clinical deterioration.

Siegel, M.J.; Patel, J.; Gado, M.H.; Shackelford, G.D.

1983-10-01T23:59:59.000Z

192

Reduced-order model for electrical impedance tomography based on proper orthogonal decomposition  

E-Print Network (OSTI)

Electrical impedance tomography (EIT) is an imaging modality in which the conductivity distribution inside a target is reconstructed based on voltage measurements from the surface of the target. Reconstructing the conductivity distribution is known to be an ill-posed inverse problem, the solutions of which are highly intolerant to modelling errors. In order to achieve sufficient accuracy, very dense meshes are usually needed in a finite element approximation of the EIT forward model. This leads to very high-dimensional problems and often unacceptably tedious computations for real-time applications. In this paper, the model reduction in EIT is considered within the Bayesian inversion framework. We construct the reduced-order model by proper orthogonal decompositions (POD) of the electrical conductivity and the potential distributions. The associated POD modes are computed based on a priori information on the conductivity. The feasibility of the reduced-order model is tested both numerically and with experimental data. In the selected test cases, the proposed model reduction approach speeds up the computation by more than two orders of magnitude in comparison with the conventional EIT reconstruction, without decreasing the quality of the reconstructed images significantly.

Antti Lipponen; Aku Seppänen; Jari Kaipio

2012-07-04T23:59:59.000Z

193

3-D Transient Hydraulic Tomography in Unconfined Aquifers with Fast Drainage Response  

SciTech Connect

We investigate, through numerical experiments, the viability of three-dimensional transient hydraulic tomography (3DTHT) for identifying the spatial distribution of groundwater flow parameters (primarily, hydraulic conductivity K) in permeable, unconfined aquifers. To invert the large amount of transient data collected from 3DTHT surveys, we utilize an iterative geostatistical inversion strategy in which outer iterations progressively increase the number of data points fitted and inner iterations solve the quasilinear geostatistical formulas of Kitanidis. In order to base our numerical experiments around realistic scenarios, we utilize pumping rates, geometries, and test lengths similar to those attainable during 3DTHT field campaigns performed at the Boise Hydrogeophysical Research Site (BHRS). We also utilize hydrologic parameters that are similar to those observed at the BHRS and in other unconsolidated, unconfined fluvial aquifers. In addition to estimating K, we test the ability of 3DTHT to estimate both average storage values (specific storage Ss and specific yield Sy) as well as spatial variability in storage coefficients. The effects of model conceptualization errors during unconfined 3DTHT are investigated including: (1) assuming constant storage coefficients during inversion and (2) assuming stationary geostatistical parameter variability. Overall, our findings indicate that estimation of K is slightly degraded if storage parameters must be jointly estimated, but that this effect is quite small compared with the degradation of estimates due to violation of ‘‘structural’’ geostatistical assumptions. Practically, we find for our scenarios that assuming constant storage values during inversion does not appear to have a significant effect on K estimates or uncertainty bounds.

Cardiff, Michael A.; Barrash, Warren

2011-12-16T23:59:59.000Z

194

Multicontrast x-ray computed tomography imaging using Talbot-Lau interferometry without phase stepping  

SciTech Connect

Purpose: The purpose of this work is to demonstrate that multicontrast computed tomography (CT) imaging can be performed using a Talbot-Lau interferometer without phase stepping, thus allowing for an acquisition scheme like that used for standard absorption CT. Methods: Rather than using phase stepping to extract refraction, small-angle scattering (SAS), and absorption signals, the two gratings of a Talbot-Lau interferometer were rotated slightly to generate a moire pattern on the detector. A Fourier analysis of the moire pattern was performed to obtain separate projection images of each of the three contrast signals, all from the same single-shot of x-ray exposure. After the signals were extracted from the detector data for all view angles, image reconstruction was performed to obtain absorption, refraction, and SAS CT images. A physical phantom was scanned to validate the proposed data acquisition method. The results were compared with a phantom scan using the standard phase stepping approach. Results: The reconstruction of each contrast mechanism produced the expected results. Signal levels and contrasts match those obtained using the phase stepping technique. Conclusions: Absorption, refraction, and SAS CT imaging can be achieved using the Talbot-Lau interferometer without the additional overhead of long scan time and phase stepping.

Bevins, Nicholas; Zambelli, Joseph; Li Ke; Qi Zhihua; Chen Guanghong [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States) and Department of Radiology, University of Wisconsin-Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States)

2012-01-15T23:59:59.000Z

195

High-resolution seismic tomography of compressional wave velocity structure at Newberry Volcano, Oregon Cascade Range  

SciTech Connect

Compressional wave velocity structure is determined for the upper crust beneath Newberry Volcano, central Oregon, using a high-resolution active-source seismic-tomography method. Newberry Volcano is a bimodal shield volcano east of the axis of the Cascade Range. It is associated both with the Cascade Range and with northwest migrating silicic volcanism in southeast Oregon. High-frequency (approx.7 Hz) crustal phases, nominally Pg and a midcrustal reflected phase, travel upward through a target volume beneath Newberry Volcano to a dense array of 120 seismographs. This arrangement is limited by station spacing to 1- to 2-km resolution in the upper 5 to 6 km of the crust beneath the volcano's summit caldera. The experiment tests the hypothesis that Cascade Range volcanoes are underlain only by small magma chambers. A small low-velocity anomaly delineated abosut 3 km below the summit caldera supports this hypothesis for Newberry Volcano and is interpreted as a possible magma chamber of a few to a few tens of km/sup 3/ in volume. A ring-shaped high-velocity anomaly nearer the surface coincides with the inner mapped ring fractures of the caldera. It also coincides with a circular gravity high, and we interpret it as largely subsolidus silicic cone sheets. The presence of this anomaly and of silicic vents along the ring fractures suggests that the fractures are a likely eruption path between the small magma chamber and the surface.

Achauer, U.; Evans, J.R.; Stauber, D.A.

1988-09-10T23:59:59.000Z

196

Seismic surface wave tomography of waste sites. 1997 annual progress report  

Science Conference Proceedings (OSTI)

'The objective of the Seismic Surface Wave Tomography of Waste Sites is to develop a robust technique for field acquisition and analysis of surface wave data for the interpretation of shallow structures, such as those associated with the burial of wastes. The analysis technique is to be developed and tested on an existing set of seismic data covering the K-901 burial site at the East Tennessee Technology Park. Also, a portable prototype for a field acquisition system will be designed and developed to obtain additional data for analysis and testing of the technique. The K-901 data have been examined and a preliminary Single Valued Decomposition inversion has been obtained. The preliminary data indicates a need for additional seismic data to ground-truth the inversion. The originally proposed gravity data acquisition has been dropped because sufficient gravity data are now available for a preliminary analysis and because the seismic data are considered more critical to the interpretation. The proposed prototype for the portable acquisition and analysis system was developed during the first year and will be used in part of the acquisition of additional seismic data.'

Long, T.L.

1997-10-14T23:59:59.000Z

197

Study of noise effects in electrical impedance tomography with resistor networks  

E-Print Network (OSTI)

We present a study of the numerical solution of the two dimensional electrical impedance tomography problem, with noisy measurements of the Dirichlet to Neumann map. The inversion uses parametrizations of the conductivity on optimal grids. The grids are optimal in the sense that finite volume discretizations on them give spectrally accurate approximations of the Dirichlet to Neumann map. The approximations are Dirichlet to Neumann maps of special resistor networks, that are uniquely recoverable from the measurements. Inversion on optimal grids has been proposed and analyzed recently, but the study of noise effects on the inversion has not been carried out. In this paper we present a numerical study of both the linearized and the nonlinear inverse problem. We take three different parametrizations of the unknown conductivity, with the same number of degrees of freedom. We obtain that the parametrization induced by the inversion on optimal grids is the most efficient of the three, because it gives the smallest standard deviation of the maximum a posteriori estimates of the conductivity, uniformly in the domain. For the nonlinear problem we compute the mean and variance of the maximum a posteriori estimates of the conductivity, on optimal grids. For small noise, we obtain that the estimates are unbiased and their variance is very close to the optimal one, given by the Cramer-Rao bound. For larger noise we use regularization and quantify the trade-off between reducing the variance and introducing bias in the solution. Both the full and partial measurement setups are considered.

Liliana Borcea; Fernando Guevara Vasquez; Alexander V. Mamonov

2011-05-05T23:59:59.000Z

198

X-Ray Energy Responses of Silicon Tomography Detectors Irradiated with Fusion Produced Neutrons  

Science Conference Proceedings (OSTI)

In order to clarify the effects of fusion-produced neutron irradiation on silicon semiconductor x-ray detectors, the x-ray energy responses of both n- and p-type silicon tomography detectors used in the Joint European Torus (JET) tokamak (n-type) and the GAMMA 10 tandem mirror (p-type) are studied using synchrotron radiation at the Photon Factory of the National Laboratory for High Energy Accelerator Research Organization (KEK). The fusion neutronics source (FNS) of Japan Atomic Energy Research Institute (JAERI) is employed as well-calibrated D-T neutron source with fluences from 10{sup 13} to 10{sup 15} neutrons/cm{sup 2} onto these semiconductor detectors. Different fluence dependence is found between these two types of detectors; that is, (i) for the n-type detector, the recovery of the degraded response is found after the neutron exposure beyond around 10{sup 13} neutrons/cm{sup 2} onto the detector. A further finding is followed as a 're-degradation' by a neutron irradiation level over about 10{sup 14} neutrons/cm{sup 2}. On the other hand, (ii) the energy response of the p-type detector shows only a gradual decrease with increasing neutron fluences. These properties are interpreted by our proposed theory on semiconductor x-ray responses in terms of the effects of neutrons on the effective doping concentration and the diffusion length of a semiconductor detector.

Kohagura, J. [Plasma Research Centre, University of Tsukuba (Japan); Cho, T. [Plasma Research Centre, University of Tsukuba (Japan); Hirata, M. [Plasma Research Centre, University of Tsukuba (Japan); Numakura, T. [Plasma Research Centre, University of Tsukuba (Japan); Yokoyama, N. [Plasma Research Centre, University of Tsukuba (Japan); Fukai, T. [Plasma Research Centre, University of Tsukuba (Japan); Tomii, Y. [Plasma Research Centre, University of Tsukuba (Japan); Tokioka, S. [Plasma Research Centre, University of Tsukuba (Japan); Miyake, Y. [Plasma Research Centre, University of Tsukuba (Japan); Kiminami, S. [Plasma Research Centre, University of Tsukuba (Japan); Shimizu, K. [Plasma Research Centre, University of Tsukuba (Japan); Miyoshi, S. [Plasma Research Centre, University of Tsukuba (Japan); Hirano, K. [High Energy Accelerator Research Organization (Japan); Yoshida, M. [Japan Atomic Energy Research Institute (Japan); Yamauchi, M. [Japan Atomic Energy Research Institute (Japan); Kondoh, T. [Japan Atomic Energy Research Institute (Japan); Nishitani, T. [Japan Atomic Energy Research Institute (Japan)

2005-01-15T23:59:59.000Z

199

Geometric classification of open-cell metal foams using X-ray micro-computed tomography  

Science Conference Proceedings (OSTI)

The geometry of foams has long been an area of interest, and a number of idealized geometric descriptions have been proposed. In order to acquire detailed, quantitative, geometric data for aluminum open-cell metal foams, X-ray {mu}CT is employed. The X-ray {mu}CT images are analyzed using specialized software, FoamView Registered-Sign , from which geometric information including strut length and pore shapes are extracted. The X-ray {mu}CT analysis allows comparison of the ideal geometric models to the actual geometric characteristics of the metal foam samples. The results reveal a high variability in ligament length, as well as features supporting the ideal geometry known as the Weaire-Phelan unit cell. The geometric findings provide information useful for improving current models of open-cell metal foam. Applications can range from predicting heat transfer or load failure to predicting liquid retention. Highlights: Black-Right-Pointing-Pointer Aluminum open-cell metal foams are geometrically classified Black-Right-Pointing-Pointer X-ray micro-computed tomography and specialized software are used to gather geometric data Black-Right-Pointing-Pointer The foams are shown to have a high variability in strut length Black-Right-Pointing-Pointer The Weaire-Phelan unit cell is shown to be a better representative of these foams.

Bock, Jessica, E-mail: bock6@illinois.edu; Jacobi, Anthony M., E-mail: a-jacobi@illinois.edu

2013-01-15T23:59:59.000Z

200

Further advancements for large area-detector based computed tomography system  

SciTech Connect

We present advancements made to a large area-detector based system for industrial x-ray computed tomography. Past performance improvements in data acquisition speeds were made by use of high-resolution large area, flat-panel amorphous-silicon (a-Si) detectors. The detectors have proven, over several years, to be a robust alternative to CCD-optics and image intensifier CT systems. These detectors also provide the advantage of area detection as compared with the single slice geometry of linear array systems. New advancements in this system include parallel processing of sinogram reconstructions, improved visualization software and migration to frame-rate a-Si detectors. Parallel processing provides significant speed improvements for data reconstruction, and is implemented for parallel-beam, fan-beam and Feldkamp cone-beam reconstruction algorithms. Reconstruction times are reduced by an order of magnitude by use of a cluster of ten or more equal-speed computers. Advancements in data visualization are made through interactive software, which allows interrogation of the full three-dimensional dataset. Inspection examples presented in this paper include an electromechanical device, a nonliving biological specimen and a press-cast plastic specimen. We also present a commonplace item for the benefit of the layperson.

Davis, A. W. (Anthony W.); Keating, S. C. (Scott C.); Claytor, T. N. (Thomas N.)

2001-01-01T23:59:59.000Z

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201

Evaluation of positron emission tomography as a method to visualize subsurface microbial processes  

Science Conference Proceedings (OSTI)

Positron emission tomography (PET) provides spatiotemporal monitoring in a nondestructive manner and has higher sensitivity and resolution relative to other tomographic methods. Therefore, this technology was evaluated for its application to monitor in situ subsurface bacterial activity. To date, however, it has not been used to monitor or image soil microbial processes. In this study, PET imaging was applied as a 'proof-of-principle' method to assess the feasibility of visualizing a radiotracer labeled subsurface bacterial strain (Rahnella sp. Y9602), previously isolated from uranium contaminated soils and shown to promote uranium phosphate precipitation. Soil columns packed with acid-purified simulated mineral soils were seeded with 2-deoxy-2-[{sup 18}F]fluoro-d-glucose ({sup 18}FDG) labeled Rahnella sp. Y9602. The applicability of [{sup 18}F]fluoride ion as a tracer for measuring hydraulic conductivity and {sup 18}FDG as a tracer to identify subsurface metabolically active bacteria was successful in our soil column studies. Our findings indicate that positron-emitting isotopes can be utilized for studies aimed at elucidating subsurface microbiology and geochemical processes important in contaminant remediation.

Kinsella K.; Schlyer D.; Kinsella, K.; Schlyer, D.J.; Fowler, J.S.; Martinez, R.J.; Sobecky, P.A.

2012-01-18T23:59:59.000Z

202

Progress in Cell Marking for Synchrotron X-ray Computed Tomography  

SciTech Connect

Recently there has been an increase in research activity into finding ways of marking cells in live animals for pre-clinical trials. Development of certain drugs and other therapies crucially depend on tracking particular cells or cell types in living systems. Therefore cell marking techniques are required which will enable longitudinal studies, where individuals can be examined several times over the course of a therapy or study. The benefits of being able to study both disease and therapy progression in individuals, rather than cohorts are clear. The need for high contrast 3-D imaging, without harming or altering the biological system requires a non-invasive yet penetrating imaging technique. The technique will also have to provide an appropriate spatial and contrast resolution. X-ray computed tomography offers rapid acquisition of 3-D images and is set to become one of the principal imaging techniques in this area. Work by our group over the last few years has shown that marking cells with gold nano-particles (GNP) is an effective means of visualising marked cells in-vivo using x-ray CT. Here we report the latest results from these studies. Synchrotron X-ray CT images of brain lesions in rats taken using the SYRMEP facility at the Elettra synchrotron in 2009 have been compared with histological examination of the tissues. Some deductions are drawn about the visibility of the gold loaded cells in both light microscopy and x-ray imaging.

Hall, Christopher [Monash Centre for Synchrotron Science, Monash University, Imaging and Medical Beam Line, Australian Synchrotron (Australia); Sturm, Erica [Department of Medical Imaging and Radiation Sciences, Monash University (Australia); Schultke, Elisabeth [Dept of Stereotactic Neurosurgery, Albert Ludwigs University of Freiburg (Germany); Arfelli, Fulvia; Astolfo, Alberto [Department of Physics, University of Trieste, Trieste (Italy); Menk, Ralf-Hendrik [Sincrotrone Trieste SCpA, Trieste (Italy); Juurlink, Bernhard H. J. [College of Medicine, Alfaisal University, Riyadh (Saudi Arabia)

2010-07-23T23:59:59.000Z

203

Design of Mega-Voltage X-ray Digital Radiography and Computed Tomography Performance Phantoms  

SciTech Connect

A number of fundamental scientific questions have arisen concerning the operation of high-energy DR and CT systems. Some of these questions include: (1) How deeply can such systems penetrate thickly shielded objects? (2) How well can such systems distinguish between dense and relatively high Z materials such as lead, tungsten and depleted uranium and lower Z materials such as steel, copper and tin? (3) How well will such systems operate for a uranium material which is an intermediate case between low density yellowcake and high density depleted uranium metal? These questions have led us to develop a set of phantoms to help answer these questions, but do not have any direct bearing on any smuggling concern. These new phantoms are designed to allow a systemic exploration of these questions by gradually varying their compositions and thicknesses. These phantoms are also good probes of the blurring behavior of radiography and tomography systems. These phantoms are composed of steel ({rho} assumed to be 7.8 g/cc), lead ({rho} assumed to be 11.4 g/cc), tungsten ({rho} assumed to be 19.25 g/cc), uranium oxide (UO{sub 3}) ({rho} assumed to be 4.6 g/cc), and depleted uranium (DU) ({rho} assumed to be 18.9 g/cc). There are five designed phantoms described in this report: (1) Cylindrical shells of Tungsten and Steel; (2) Depleted Uranium Inside Tungsten Hemi-cube Shells; (3) Nested Spherical Shells; (4) UO{sub 3} Cylinder; and (5) Shielded DU Sphere.

Aufderheide, M B; Martz, H E; Curtin, M

2009-06-22T23:59:59.000Z

204

Patient self-attenuation and technologist dose in positron emission tomography  

SciTech Connect

Positron emission tomography (PET), with 511-keV radiation and long patient-uptake times, presents unique radiation safety concerns. This two-part study considers aspects of PET radiation safety as they relate to PET suite design, dose to the public, and technologist occupational dose. In the first part of the study, the self-attenuation of radiation by patients' bodies was quantified. The radiation exposure was measured at three positions from 64 patients injected with fluorine-18 fluorodeoxyglucose (FDG) during the uptake period. Compared with an in vitro control used as a point source, a significant decrease in exposure (>40% at 1 m) was observed due to nonuniform distribution of FDG and attenuation within the patients. The attenuation data are consistent with results from simulations [M. E. Phelps, ''Comments and Perspectives,'' J. Nucl. Med. 45, 1601 (2004)] that treat the body as a uniform, water-filled cylinder. As distance is often the principal source of protection for 511-keV radiation, the considerable self-attenuation may allow for more compact PET suites. However, despite high patient self-attenuation, shielding, and standard precautionary measures, PET technologist occupational doses can remain quite high ({approx}12 mSv/year). The second part of this study tracked the daily dose received by PET technologists. Close technologist-patient interaction both during and following FDG administration, as much as 20 min/study, contribute to the high doses and point to the need for a more innovative approach to radiation protection for PET technologists.

Zeff, Benjamin W.; Yester, Michael V. [Department of Radiology, University of Alabama at Birmingham, Birmingham, Alabama 35233 (United States)

2005-04-01T23:59:59.000Z

205

Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins  

SciTech Connect

In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory s (INL s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

Hausladen, Paul [ORNL; Blackston, Matthew A [ORNL; Brubaker, E. [Sandia National Laboratories (SNL); Chichester, David [Idaho National Laboratory (INL); Marleau, P. [Sandia National Laboratories (SNL); Newby, Robert Jason [ORNL

2012-01-01T23:59:59.000Z

206

Positron Emission Tomography (PET) Evaluation After Initial Chemotherapy and Radiation Therapy Predicts Local Control in Rhabdomyosarcoma  

Science Conference Proceedings (OSTI)

Purpose: 18-fluorodeoxyglucose positron emission tomography (PET) is already an integral part of staging in rhabdomyosarcoma. We investigated whether primary-site treatment response characterized by serial PET imaging at specific time points can be correlated with local control. Patients and Methods: We retrospectively examined 94 patients with rhabdomyosarcoma who received initial chemotherapy 15 weeks (median) before radiotherapy and underwent baseline, preradiation, and postradiation PET. Baseline PET standardized uptake values (SUVmax) and the presence or absence of abnormal uptake (termed PET-positive or PET-negative) both before and after radiation were examined for the primary site. Local relapse-free survival (LRFS) was calculated according to baseline SUVmax, PET-positive status, and PET-negative status by the Kaplan-Meier method, and comparisons were tested with the log-rank test. Results: The median patient age was 11 years. With 3-year median follow-up, LRFS was improved among postradiation PET-negative vs PET-positive patients: 94% vs 75%, P=.02. By contrast, on baseline PET, LRFS was not significantly different for primary-site SUVmax {7 (median), although the findings suggested a trend toward improved LRFS: 96% for SUVmax {7, P=.08. Preradiation PET also suggested a statistically insignificant trend toward improved LRFS for PET-negative (97%) vs PET-positive (81%) patients (P=.06). Conclusion: Negative postradiation PET predicted improved LRFS. Notably, 77% of patients with persistent postradiation uptake did not experience local failure, suggesting that these patients could be closely followed up rather than immediately referred for intervention. Negative baseline and preradiation PET findings suggested statistically insignificant trends toward improved LRFS. Additional study may further understanding of relationships between PET findings at these time points and outcome in rhabdomyosarcoma.

Dharmarajan, Kavita V., E-mail: dharmark@mskcc.org [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States); Wexler, Leonard H.; Gavane, Somali; Fox, Josef J.; Schoder, Heiko; Tom, Ashlyn K.; Price, Alison N.; Meyers, Paul A.; Wolden, Suzanne L. [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States)] [Departments of Radiation Oncology, Pediatric Oncology, and Nuclear Medicine, Memorial Sloan-Kettering, New York, New York (United States)

2012-11-15T23:59:59.000Z

207

Demonstration of Emitted-Neutron Computed Tomography to Count Fuel Pins  

Science Conference Proceedings (OSTI)

In this paper, we report demonstration of emitted-neutron computed tomography using fast fission neutrons to infer the geometry of sources of special nuclear material (SNM) such as fuel pins. In a proof-of-concept measurement at the Idaho National Laboratory’s (INL’s) Zero Power Physics Reactor (ZPPR) facility, an array of unirradiated Pu MOX fuel rodlets in a soup can were imaged, and a bias defect consisting of a single rodlet containing Pu replaced by one containing depleted uranium (DU) was detected. The imaging system employed in the demonstration is based on a newly constructed array of pixelated neutron detectors that are suitable for arrangement in a close-packed imaging array and whose active volume consists of liquid scintillator EJ-309 which allows neutron-gamma discrimination via pulse shape to enable pure fast-neutron imaging. The imaging array was used along with a radial collimator aperture in order to perform high quality fast-neutron imaging where tomographic reconstruction of slices through an object resolve neutron sources similar in dimension to a fuel pellet, or about 1 cm. Measurements were performed at Oak Ridge National Laboratory (ORNL) with neutron sources in addition to those performed at the INL’s ZPPR facility with Pu MOX fuel rodlets. An analogous capability to detect single-pin defects in spent fuel assemblies would be desirable, such as for safeguards verification measurements of spent fuel assemblies just prior to transferring them from the spent fuel cooling pool to long term dry cask storage. This paper describes the design and construction of the present imager, characterization measurements with neutron sources at ORNL, measurements with SNM at INL’s ZPPR facility, and feasibility of building an analogous imager for spent fuel measurements.

P. A. Hausladen; M. A. Blackston; E. Brubaker; D. L. Chichester; P. Marleau; R. J. Newby

2012-07-01T23:59:59.000Z

208

Efficacy of Lower-Body Shielding in Computed Tomography Fluoroscopy-Guided Interventions  

Science Conference Proceedings (OSTI)

Purpose: Computed tomography (CT) fluoroscopy-guided interventions pose relevant radiation exposure to the interventionalist. The goal of this study was to analyze the efficacy of lower-body shielding as a simple structural method for decreasing radiation dose to the interventionalist without limiting access to the patient. Material and Methods: All examinations were performed with a 128-slice dual source CT scanner (12 Multiplication-Sign 1.2-mm collimation; 120 kV; and 20, 40, 60, and 80 mAs) and an Alderson-Rando phantom. Scatter radiation was measured with an ionization chamber and a digital dosimeter at standardized positions and heights with and without a lower-body lead shield (0.5-mm lead equivalent; Kenex, Harlow, UK). Dose decreases were computed for the different points of measurement. Results: On average, lower-body shielding decreased scatter radiation by 38.2% within a 150-cm radius around the shielding. This decrease is most significant close to the gantry opening and at low heights of 50 and 100 cm above the floor with a maximum decrease of scatter radiation of 95.9% close to the scanner's isocentre. With increasing distance to the gantry opening, the effect decreased. There is almost no dose decrease effect at {>=}150 above the floor. Scatter radiation and its decrease were linearly correlated with the tube current-time product (r{sup 2} = 0.99), whereas percent scatter radiation decrease was independent of the tube current-time product. Conclusion: Lower-body shielding is an effective way to decrease radiation exposure to the interventionalist and should routinely be used in CT fluoroscopy-guided interventions.

Mahnken, Andreas H., E-mail: mahnken@rad.rwth-aachen.de [RWTH Aachen, Department of Diagnostic and Interventional Radiology (Germany); Sedlmair, Martin [Siemens, Healthcare Sector (Germany); Ritter, Christine [University of Copenhagen, Niels Bohr Institute (Denmark); Banckwitz, Rosemarie; Flohr, Thomas [Siemens, Healthcare Sector (Germany)

2012-12-15T23:59:59.000Z

209

PILOT-SCALE FIELD VALIDATION OF THE LONG ELECTRODE ELECTRICAL RESISTIVITY TOMOGRAPHY METHOD  

SciTech Connect

Field validation for the long electrode electrical resistivity tomography (LE-ERT) method was attempted in order to demonstrate the performance of the technique in imaging a simple buried target. The experiment was an approximately 1/17 scale mock-up of a region encompassing a buried nuclear waste tank on the Hanford site. The target of focus was constructed by manually forming a simulated plume within the vadose zone using a tank waste simulant. The LE-ERT results were compared to ERT using conventional point electrodes on the surface and buried within the survey domain. Using a pole-pole array, both point and long electrode imaging techniques identified the lateral extents of the pre-formed plume with reasonable fidelity, but the LE-ERT was handicapped in reconstructing the vertical boundaries. The pole-dipole and dipole-dipole arrays were also tested with the LE-ERT method and were shown to have the least favorable target properties, including the position of the reconstructed plume relative to the known plume and the intensity of false positive targets. The poor performance of the pole-dipole and dipole-dipole arrays was attributed to an inexhaustive and non-optimal coverage of data at key electrodes, as well as an increased noise for electrode combinations with high geometric factors. However, when comparing the model resolution matrix among the different acquisition strategies, the pole-dipole and dipole-dipole arrays using long electrodes were shown to have significantly higher average and maximum values than any pole-pole array. The model resolution describes how well the inversion model resolves the subsurface. Given the model resolution performance of the pole-dipole and dipole-dipole arrays, it may be worth investing in tools to understand the optimum subset of randomly distributed electrode pairs to produce maximum performance from the inversion model.

GLASER DR; RUCKER DF; CROOK N; LOKE MH

2011-07-14T23:59:59.000Z

210

Nonrigid registration-based coronary artery motion correction for cardiac computed tomography  

SciTech Connect

Purpose: X-ray computed tomography angiography (CTA) is the modality of choice to noninvasively monitor and diagnose heart disease with coronary artery health and stenosis detection being of particular interest. Reliable, clinically relevant coronary artery imaging mandates high spatiotemporal resolution. However, advances in intrinsic scanner spatial resolution (CT scanners are available which combine nearly 900 detector columns with focal spot oversampling) can be tempered by motion blurring, particularly in patients with unstable heartbeats. As a result, recently numerous methods have been devised to improve coronary CTA imaging. Solutions involving hardware, multisector algorithms, or {beta}-blockers are limited by cost, oversimplifying assumptions about cardiac motion, and populations showing contraindications to drugs, respectively. This work introduces an inexpensive algorithmic solution that retrospectively improves the temporal resolution of coronary CTA without significantly affecting spatial resolution. Methods: Given the goal of ruling out coronary stenosis, the method focuses on 'deblurring' the coronary arteries. The approach makes no assumptions about cardiac motion, can be used on exams acquired at high heart rates (even over 75 beats/min), and draws on a fast and accurate three-dimensional (3D) nonrigid bidirectional labeled point matching approach to estimate the trajectories of the coronary arteries during image acquisition. Motion compensation is achieved by employing a 3D warping of a series of partial reconstructions based on the estimated motion fields. Each of these partial reconstructions is created from data acquired over a short time interval. For brevity, the algorithm 'Subphasic Warp and Add' (SWA) reconstruction. Results: The performance of the new motion estimation-compensation approach was evaluated by a systematic observer study conducted using nine human cardiac CTA exams acquired over a range of average heart rates between 68 and 86 beats/min. Algorithm performance was based-lined against exams reconstructed using standard filtered-backprojection (FBP). The study was performed by three experienced reviewers using the American Heart Association's 15-segment model. All vessel segments were evaluated to quantify their viability to allow a clinical diagnosis before and after motion estimation-compensation using SWA. To the best of the authors' knowledge this is the first such observer study to show that an image processing-based software approach can improve the clinical diagnostic value of CTA for coronary artery evaluation. Conclusions: Results from the observer study show that the SWA method described here can dramatically reduce coronary artery motion and preserve real pathology, without affecting spatial resolution. In particular, the method successfully mitigated motion artifacts in 75% of all initially nondiagnostic coronary artery segments, and in over 45% of the cases this improvement was enough to make a previously nondiagnostic vessel segment clinically diagnostic.

Bhagalia, Roshni; Pack, Jed D.; Miller, James V.; Iatrou, Maria [GE Global Research, Niskayuna, New York 12309 (United States); GE Healthcare, Hoboken, New Jersey 07030 (United States)

2012-07-15T23:59:59.000Z

211

A fully 3D approach for metal artifact reduction in computed tomography  

SciTech Connect

Purpose: In computed tomography imaging metal objects in the region of interest introduce inconsistencies during data acquisition. Reconstructing these data leads to an image in spatial domain including star-shaped or stripe-like artifacts. In order to enhance the quality of the resulting image the influence of the metal objects can be reduced. Here, a metal artifact reduction (MAR) approach is proposed that is based on a recomputation of the inconsistent projection data using a fully three-dimensional Fourier-based interpolation. The success of the projection space restoration depends sensitively on a sensible continuation of neighboring structures into the recomputed area. Fortunately, structural information of the entire data is inherently included in the Fourier space of the data. This can be used for a reasonable recomputation of the inconsistent projection data. Methods: The key step of the proposed MAR strategy is the recomputation of the inconsistent projection data based on an interpolation using nonequispaced fast Fourier transforms (NFFT). The NFFT interpolation can be applied in arbitrary dimension. The approach overcomes the problem of adequate neighborhood definitions on irregular grids, since this is inherently given through the usage of higher dimensional Fourier transforms. Here, applications up to the third interpolation dimension are presented and validated. Furthermore, prior knowledge may be included by an appropriate damping of the transform during the interpolation step. This MAR method is applicable on each angular view of a detector row, on two-dimensional projection data as well as on three-dimensional projection data, e.g., a set of sequential acquisitions at different spatial positions, projection data of a spiral acquisition, or cone-beam projection data. Results: Results of the novel MAR scheme based on one-, two-, and three-dimensional NFFT interpolations are presented. All results are compared in projection data space and spatial domain with the well-known one-dimensional linear interpolation strategy. Conclusions: In conclusion, it is recommended to include as much spatial information into the recomputation step as possible. This is realized by increasing the dimension of the NFFT. The resulting image quality can be enhanced considerably.

Kratz, Baerbel; Weyers, Imke; Buzug, Thorsten M. [Institute of Medical Engineering, University of Luebeck, Luebeck 23562 (Germany); Institute of Anatomy, University of Luebeck, Luebeck 23562 (Germany); Institute of Medical Engineering, University of Luebeck, Luebeck 23562 (Germany)

2012-11-15T23:59:59.000Z

212

Kilovoltage Rotational External Beam Radiotherapy on a Breast Computed Tomography Platform: A Feasibility Study  

SciTech Connect

Purpose: To demonstrate the feasibility of a dedicated breast computed tomography (bCT) platform to deliver rotational kilovoltage (kV) external beam radiotherapy (RT) for partial breast irradiation, whole breast irradiation, and dose painting. Methods and Materials: Rotational kV-external beam RT using the geometry of a prototype bCT platform was evaluated using a Monte Carlo simulator. A point source emitting 178 keV photons (approximating a 320-kVp spectrum with 4-mm copper filtration) was rotated around a 14-cm voxelized polyethylene disk (0.1 cm tall) or cylinder (9 cm tall) to simulate primary and primary plus scattered photon interactions, respectively. Simulations were also performed using voxelized bCT patient images. Beam collimation was varied in the x-y plane (1-14 cm) and in the z-direction (0.1-10 cm). Dose painting for multiple foci, line, and ring distributions was demonstrated using multiple rotations with varying beam collimation. Simulations using the scanner's native hardware (120 kVp filtered by 0.2-mm copper) were validated experimentally. Results: As the x-y collimator was narrowed, the two-dimensional dose profiles shifted from a cupped profile with a high edge dose to an increasingly peaked central dose distribution with a sharp dose falloff. Using a 1-cm beam, the cylinder edge dose was <7% of the dose deposition at the cylinder center. Simulations using 120-kVp X-rays showed distributions similar to the experimental measurements. A homogeneous dose distribution (<2.5% dose fluctuation) with a 20% decrease in dose deposition at the cylinder edge (i.e., skin sparing) was demonstrated by weighted summation of four dose profiles using different collimation widths. Simulations using patient bCT images demonstrated the potential for treatment planning and image-guided RT. Conclusions: Rotational kV-external beam RT for partial breast irradiation, dose painting, and whole breast irradiation with skin sparing is feasible on a bCT platform with the potential for high-resolution image-guided RT.

Prionas, Nicolas D.; McKenney, Sarah E. [Department of Radiology, University of California, Davis, Medical Center, Sacramento, California (United States)] [Department of Radiology, University of California, Davis, Medical Center, Sacramento, California (United States); Stern, Robin L. [Department of Radiation Oncology, University of California, Davis, Medical Center, Sacramento, California (United States)] [Department of Radiation Oncology, University of California, Davis, Medical Center, Sacramento, California (United States); Boone, John M., E-mail: jmboone@ucdavis.edu [Department of Radiology, University of California, Davis, Medical Center, Sacramento, California (United States)

2012-10-01T23:59:59.000Z

213

Improved fluorescence-enhanced optical imaging and tomography by enhanced excitation light rejection  

E-Print Network (OSTI)

Fluorescence enhanced optical imaging and tomography studies involve the detection of weak fluorescent signals emanating from nano- to picomolar concentrations of exogenous or endogenously produced fluorophore concurrent with the rejection of an overwhelmingly large component of backscattered excitation light. The elimination of the back-reflected excitation light of the collected signal remains a major and often unrecognized challenge for further reducing the noise floor and increasing sensitivity of small animal fluorescence imaging. In this dissertation, we adapted collimating and gradient index (GRIN) lenses in an existing frequency-domain system to improve excitation light rejection and enhance planar and tomographic imaging. To achieve this goal, we developed planar and tomographic imaging systems based upon ray tracing calculations for improved rejection of excitation light. The “out-of-band (S (?x))” to “in-band (S (?m) - S (?x))” signal ratio assessing excitation leakage was acquired with and without collimating optics. The addition of collimating optics resulted in a 51 to 75% reduction in the transmission ratio of (S (?x))/ (S (?m) - S (?x)) for the phantom studies and an increase of target to background ratio (TBR) from 11% to 31% in animal studies. Additionally, we presented results demonstrating the improvement of model match between experiments and forward simulation models by adaptation of GRIN lens optics to a breast phantom study. In particular, 128 GRIN lenses on the fiber bundle face were employed to align the collected excitation and emission light normal to the filter surface in an existing frequency-domain system. As a result of GRIN lens collimation, we reduced the transmission ratio between 10 and 86 % and improved the model match for tomographic reconstruction of one (1 cm3) and two (0.1 cm3) targets in a 1087 cm3 of breast phantom. Ultimately, this work improves the sensitivity of NIR fluorescence imaging by enhancing the rejection of excitation light and shows that the current sensitivity challenges for translating fluorescence-enhanced optical imaging into the clinic can be overcome.

Hwang, Kil Dong

2006-12-01T23:59:59.000Z

214

Low-dose computed tomography image restoration using previous normal-dose scan  

Science Conference Proceedings (OSTI)

Purpose: In current computed tomography (CT) examinations, the associated x-ray radiation dose is of a significant concern to patients and operators. A simple and cost-effective means to perform the examinations is to lower the milliampere-seconds (mAs) or kVp parameter (or delivering less x-ray energy to the body) as low as reasonably achievable in data acquisition. However, lowering the mAs parameter will unavoidably increase data noise and the noise would propagate into the CT image if no adequate noise control is applied during image reconstruction. Since a normal-dose high diagnostic CT image scanned previously may be available in some clinical applications, such as CT perfusion imaging and CT angiography (CTA), this paper presents an innovative way to utilize the normal-dose scan as a priori information to induce signal restoration of the current low-dose CT image series. Methods: Unlike conventional local operations on neighboring image voxels, nonlocal means (NLM) algorithm utilizes the redundancy of information across the whole image. This paper adapts the NLM to utilize the redundancy of information in the previous normal-dose scan and further exploits ways to optimize the nonlocal weights for low-dose image restoration in the NLM framework. The resulting algorithm is called the previous normal-dose scan induced nonlocal means (ndiNLM). Because of the optimized nature of nonlocal weights calculation, the ndiNLM algorithm does not depend heavily on image registration between the current low-dose and the previous normal-dose CT scans. Furthermore, the smoothing parameter involved in the ndiNLM algorithm can be adaptively estimated based on the image noise relationship between the current low-dose and the previous normal-dose scanning protocols. Results: Qualitative and quantitative evaluations were carried out on a physical phantom as well as clinical abdominal and brain perfusion CT scans in terms of accuracy and resolution properties. The gain by the use of the previous normal-dose scan via the presented ndiNLM algorithm is noticeable as compared to a similar approach without using the previous normal-dose scan. Conclusions: For low-dose CT image restoration, the presented ndiNLM method is robust in preserving the spatial resolution and identifying the low-contrast structure. The authors can draw the conclusion that the presented ndiNLM algorithm may be useful for some clinical applications such as in perfusion imaging, radiotherapy, tumor surveillance, etc.

Ma, Jianhua; Huang, Jing; Feng, Qianjin; Zhang, Hua; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan [Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China and Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China); Department of Biomedical Engineering, Fourth Military Medical University, Xi'An, Shanxi 710032 (China); Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China)

2011-10-15T23:59:59.000Z

215

Segmentation and quantification of materials with energy discriminating computed tomography: A phantom study  

Science Conference Proceedings (OSTI)

Purpose: To experimentally investigate whether a computed tomography (CT) system based on CdZnTe (CZT) detectors in conjunction with a least-squares parameter estimation technique can be used to decompose four different materials. Methods: The material decomposition process was divided into a segmentation task and a quantification task. A least-squares minimization algorithm was used to decompose materials with five measurements of the energy dependent linear attenuation coefficients. A small field-of-view energy discriminating CT system was built. The CT system consisted of an x-ray tube, a rotational stage, and an array of CZT detectors. The CZT array was composed of 64 pixels, each of which is 0.8x0.8x3 mm. Images were acquired at 80 kVp in fluoroscopic mode at 50 ms per frame. The detector resolved the x-ray spectrum into energy bins of 22-32, 33-39, 40-46, 47-56, and 57-80 keV. Four phantoms were constructed from polymethylmethacrylate (PMMA), polyethylene, polyoxymethylene, hydroxyapatite, and iodine. Three phantoms were composed of three materials with embedded hydroxyapatite (50, 150, 250, and 350 mg/ml) and iodine (4, 8, 12, and 16 mg/ml) contrast elements. One phantom was composed of four materials with embedded hydroxyapatite (150 and 350 mg/ml) and iodine (8 and 16 mg/ml). Calibrations consisted of PMMA phantoms with either hydroxyapatite (100, 200, 300, 400, and 500 mg/ml) or iodine (5, 15, 25, 35, and 45 mg/ml) embedded. Filtered backprojection and a ramp filter were used to reconstruct images from each energy bin. Material segmentation and quantification were performed and compared between different phantoms. Results: All phantoms were decomposed accurately, but some voxels in the base material regions were incorrectly identified. Average quantification errors of hydroxyapatite/iodine were 9.26/7.13%, 7.73/5.58%, and 12.93/8.23% for the three-material PMMA, polyethylene, and polyoxymethylene phantoms, respectively. The average errors for the four-material phantom were 15.62% and 2.76% for hydroxyapatite and iodine, respectively. Conclusions: The calibrated least-squares minimization technique of decomposition performed well in breast imaging tasks with an energy resolving detector. This method can provide material basis images containing concentrations of the relevant materials that can potentially be valuable in the diagnostic process.

Le, Huy Q.; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

2011-01-15T23:59:59.000Z

216

Muon Collider Papers and Reports  

NLE Websites -- All DOE Office Websites (Extended Search)

of muon collider papers and reports. Muon Collider Feasibilty Study ... Snowmass Book BNL Muon Collider Project Publication Index Fermilab Muon Collider Notes Muon Collider...

217

(/sup 11/C)clorgyline and (/sup 11/C)-L-deprenyl and their use in measuring functional monoamine oxidase activity in the brain using positron emission tomography  

DOE Patents (OSTI)

This invention involves a new strategy for imaging the activity of the enzyme monoamine oxidase in the living body by using /sup 11/C-labeled enzyme inhibitors which bind irreversibly to an enzyme as a result of catalysis. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography. 2 figs.

Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.

1986-04-17T23:59:59.000Z

218

Fermilab | Muon Collider | Graphics  

NLE Websites -- All DOE Office Websites (Extended Search)

Graphics A chain of accelerators and other devices is necessary to produce and accelerate muons before scientists can make muons collide. Click image for larger version A muon...

219

Assessment of cardiac single-photon emission computed tomography performance using a scanning linear observer  

SciTech Connect

Purpose: Single-photon emission computed tomography (SPECT) is widely used to detect myocardial ischemia and myocardial infarction. It is important to assess and compare different SPECT system designs in order to achieve the highest detectability of cardiac defects. Methods: Whitaker et al.'s study ['Estimating random signal parameters from noisy images with nuisance parameters: linear and scanning-linear methods,' Opt. Express 16(11), 8150-8173 (2008)] on the scanning linear observer (SLO) shows that the SLO can be used to estimate the location and size of signals. One major advantage of the SLO is that it can be used with projection data rather than with reconstruction data. Thus, this observer model assesses the overall hardware performance independent of any reconstruction algorithm. In addition, the computation time of image quality studies is significantly reduced. In this study, three systems based on the design of the GE cadmium zinc telluride-based dedicated cardiac SPECT camera Discovery 530c were assessed. This design, which is officially named the Alcyone Technology: Discovery NM 530c, was commercialized in August, 2009. The three systems, GE27, GE19, and GE13, contain 27, 19, and 13 detectors, respectively. Clinically, a human heart can be virtually segmented into three coronary artery territories: the left-anterior descending artery, left-circumflex artery, and right coronary artery. One of the most important functions of a cardiac SPECT system is to produce images from which a radiologist can accurately predict in which territory the defect exists [http://www.asnc.org/media/PDFs/PPReporting081511.pdf, Guideline from American Society of Nuclear Cardiology]. A good estimation of the extent of the defect from the projection images is also very helpful for determining the seriousness of the myocardial ischemia. In this study, both the location and extent of defects were estimated by the SLO, and the system performance was assessed by localization receiver operating characteristic (LROC) [P. Khurd and G. Gindi, 'Decision strategies maximizing the area under the LROC curve,' Proc. SPIE 5749, 150-161 (2005)] or estimation receiver operating characteristic (EROC) [E. Clarkson, 'Estimation receiver operating characteristic curve and ideal observers for combined detection/estimation tasks,' J. Opt. Soc. Am. A 24, B91-B98 (2007)] curves. Results: The area under the LROC/EROC curve (AULC/AUEC) and the true positive fraction (TPF) at a specific false positive fraction (FPF) can be treated as the figures of merit. For radii estimation with a 1 mm tolerance, the AUEC values of the GE27, GE19, and GE13 systems are 0.8545, 0.8488, and 0.8329, and the TPF at FPF = 5% are 77.1%, 76.46%, and 73.55%, respectively. The assessment of all three systems revealed that the GE19 system yields estimated information and cardiac defect detectability very close to those of the GE27 system while using eight fewer detectors. Thus, 30% of the expensive detector units can be removed with confidence. Conclusions: As the results show, a combination of the SLO and LROC/EROC curves can determine the configuration that yields the most relevant estimation/detection information. Thus, this is a useful method for assessing cardiac SPECT systems.

Lee, Chih-Jie; Kupinski, Matthew A.; Volokh, Lana [College of Optical Sciences, University of Arizona, Tucson, Arizona 85721 (United States); GE Healthcare, Haifa 39120 (Israel)

2013-01-15T23:59:59.000Z

220

Organ doses for reference pediatric and adolescent patients undergoing computed tomography estimated by Monte Carlo simulation  

SciTech Connect

Purpose: To establish an organ dose database for pediatric and adolescent reference individuals undergoing computed tomography (CT) examinations by using Monte Carlo simulation. The data will permit rapid estimates of organ and effective doses for patients of different age, gender, examination type, and CT scanner model. Methods: The Monte Carlo simulation model of a Siemens Sensation 16 CT scanner previously published was employed as a base CT scanner model. A set of absorbed doses for 33 organs/tissues normalized to the product of 100 mAs and CTDI{sub vol} (mGy/100 mAs mGy) was established by coupling the CT scanner model with age-dependent reference pediatric hybrid phantoms. A series of single axial scans from the top of head to the feet of the phantoms was performed at a slice thickness of 10 mm, and at tube potentials of 80, 100, and 120 kVp. Using the established CTDI{sub vol}- and 100 mAs-normalized dose matrix, organ doses for different pediatric phantoms undergoing head, chest, abdomen-pelvis, and chest-abdomen-pelvis (CAP) scans with the Siemens Sensation 16 scanner were estimated and analyzed. The results were then compared with the values obtained from three independent published methods: CT-Expo software, organ dose for abdominal CT scan derived empirically from patient abdominal circumference, and effective dose per dose-length product (DLP). Results: Organ and effective doses were calculated and normalized to 100 mAs and CTDI{sub vol} for different CT examinations. At the same technical setting, dose to the organs, which were entirely included in the CT beam coverage, were higher by from 40 to 80% for newborn phantoms compared to those of 15-year phantoms. An increase of tube potential from 80 to 120 kVp resulted in 2.5-2.9-fold greater brain dose for head scans. The results from this study were compared with three different published studies and/or techniques. First, organ doses were compared to those given by CT-Expo which revealed dose differences up to several-fold when organs were partially included in the scan coverage. Second, selected organ doses from our calculations agreed to within 20% of values derived from empirical formulae based upon measured patient abdominal circumference. Third, the existing DLP-to-effective dose conversion coefficients tended to be smaller than values given in the present study for all examinations except head scans. Conclusions: A comprehensive organ/effective dose database was established to readily calculate doses for given patients undergoing different CT examinations. The comparisons of our results with the existing studies highlight that use of hybrid phantoms with realistic anatomy is important to improve the accuracy of CT organ dosimetry. The comprehensive pediatric dose data developed here are the first organ-specific pediatric CT scan database based on the realistic pediatric hybrid phantoms which are compliant with the reference data from the International Commission on Radiological Protection (ICRP). The organ dose database is being coupled with an adult organ dose database recently published as part of the development of a user-friendly computer program enabling rapid estimates of organ and effective dose doses for patients of any age, gender, examination types, and CT scanner model.

Lee, Choonsik; Kim, Kwang Pyo; Long, Daniel J.; Bolch, Wesley E. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20852 (United States); Department of Nuclear Engineering, Kyung Hee University, Gyeonggi-do, 446906 (Korea, Republic of); J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611 (United States)

2012-04-15T23:59:59.000Z

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221

Muon muon collider: Feasibility study  

Science Conference Proceedings (OSTI)

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup {minus}2} s{sup {minus}1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice--the authors believe--to allow them to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring which has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design.

NONE

1996-06-18T23:59:59.000Z

222

Positron Emission Tomography for Assessing Local Failure After Stereotactic Body Radiotherapy for Non-Small-Cell Lung Cancer  

Science Conference Proceedings (OSTI)

Purpose: We analyzed whether positron emission tomography (PET)/computed tomography standardized uptake values (SUVs) after stereotactic body radiotherapy (SBRT) could predict local recurrence (LR) in non-small-cell lung cancer (NSCLC). Methods and Materials: This study comprised 128 patients with Stage I (n = 68) or isolated recurrent/secondary parenchymal (n = 60) NSCLC treated with image-guided SBRT to 50 Gy over 4 consecutive days; prior radiotherapy was allowed. PET/computed tomography scans were obtained before therapy and at 1 to 6 months after therapy, as well as subsequently as clinically indicated. Continuous variables were analyzed with Kruskal-Wallis tests and categorical variables with Pearson chi-square or Fisher exact tests. Actuarial local failure rates were calculated with the Kaplan-Meier method. Results: At a median follow-up of 31 months (range, 6-71 months), the actuarial 1-, 2-, and 3-year local control rates were 100%, 98.5%, and 98.5%, respectively, in the Stage I group and 95.8%, 87.6%, and 85.8%, respectively, in the recurrent group. The cumulative rates of regional nodal recurrence and distant metastasis were 8.8% (6 of 68) and 14.7% (10 of 68), respectively, for the Stage I group and 11.7% (7 of 60) and 16.7% (10 of 60), respectively, for the recurrent group. Univariate analysis showed that SUVs obtained 12.1 to 24 months after treatment for the Stage I group (p = 0.007) and 6.1 to 12 months and 12.1 to 24 months after treatment for the recurrent group were associated with LR (p < 0.001 for both). Of the 128 patients, 17 (13.3%) had ipsilateral consolidation after SBRT but no elevated metabolic activity on PET; none had LR. The cutoff maximum SUV of 5 was found to have 100% sensitivity, 91% specificity, a 50% positive predictive value, and a 100% negative predictive value for predicting LR. Conclusions: PET was helpful for distinguishing SBRT-induced consolidation from LR. SUVs obtained more than 6 months after SBRT for NSCLC were associated with local failure. A maximum SUV greater than 5, especially at more than 6 months after SBRT, should prompt biopsy to rule out LR.

Zhang Xu; Liu Hui [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Balter, Peter [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Allen, Pamela K.; Komaki, Ritsuko [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Pan, Tinsu [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Imaging Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Chuang, Hubert H. [Department of Nuclear Medicine, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Nuclear Medicine, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2012-08-01T23:59:59.000Z

223

Advanced characterization of physical properties of coals with different coal structures by nuclear magnetic resonance and X-ray computed tomography  

Science Conference Proceedings (OSTI)

In order to understand the correlation between coal structure and physical property of coal, samples with different coal structures were collected from the Late Permian period coal seams in the Laochang area, Yunnan Province, China. A set of experiments ... Keywords: Adsorption capacities, Coal structure, Nuclear magnetic resonance (NMR), Seepage capacities, X-ray computed tomography (X-CT)

Song Li; Dazhen Tang; Hao Xu; Zi Yang

2012-11-01T23:59:59.000Z

224

Quantitative discrimination between geological materials with variable density contrast by high resolution X-ray computed tomography: An example using amygdule size-distribution in ancient lava flows  

Science Conference Proceedings (OSTI)

The bubble-size distribution in 2.7 billion year old lava flows can be used as a proof of concept illustrating a new set of techniques for measuring volumes of geological materials with variable density contrasts using high-resolution X-ray computed ... Keywords: Amygdules, Bootstrap resampling, Bubble-size distribution, Central limit theorem, Dynamic thresholding, X-ray tomography

Sanjoy M. Som, James W. Hagadorn, Weston A. Thelen, Alan R. Gillespie, David C. Catling, Roger Buick

2013-04-01T23:59:59.000Z

225

Computerized axial tomography of the chest for visualization of ''absent'' pulmonary arteries  

SciTech Connect

To expand the search for central pulmonary arteries in six patients with absence of cardiac-pulmonary continuity, computerized axial tomography (CAT) of the chest was performed. The CAT scans were compared with previous arteriograms and pulmonary vein wedge angiograms. Three patients with type IV truncus arteriosus were studied, and none had a central, right or left pulmonary artery on CAT scan. However, two patients with tetralogy of Fallot with pulmonary atresia and a patent ductus arteriosus to the right lung demonstrated the presence of a left pulmonary artery. In addition, one child with truncus arteriosus with ''absent'' left pulmonary artery demonstrated a left pulmonary artery on the CAT scan. The CAT scan may therefore enhance our ability to search for disconnected pulmonary arteries in children with complex cyanotic congenital heart disease.

Sondheimer, H.M. (Upstate Medical Center, Syracuse, NY); Oliphant, M.; Schneider, B.; Kavey, R.E.W.; Blackman, M.S.; Parker, F.B. Jr.

1982-05-01T23:59:59.000Z

226

Sub-millimeter nuclear medical imaging with reduced dose application in positron emission tomography using beta-gamma coincidences  

E-Print Network (OSTI)

Positron emission tomography (PET) permits a functional understanding of the underlying causes of many diseases. Modern whole-body PET systems reach a spatial resolution of 2-6 mm (FWHM). A limitation of this technique occurs from the thermalization and diffusion of the positron before its annihilation, typically within the mm range. We present a nuclear medical imaging technique, able to reach sub-millimeter spatial resolution in 3 dimensions with a reduced effective dose application compared to conventional PET. This 'gamma-PET' technique draws on specific medical isotopes, simultaneously emitting an additional photon accompanying the beta^+ decay. Exploiting the triple coincidence between the positron annihilation and the third photon, it is possible to separate the reconstructed 'true' events from background. In order to characterize the potential of this technique, MC simulations and image reconstructions have been performed. The achievable spatial resolution has been found to reach ca. 0.4 mm (FWHM) in ...

Lang, C; Parodi, K; Thirolf, P G

2013-01-01T23:59:59.000Z

227

The Application of Monochromatic Energies to Investigate Multiphase Porous Media Systems using Synchrotron X-ray Tomography  

SciTech Connect

X-ray computed tomography (CT) is becoming a useful tool for nondestructive imaging of many geoenvironmental and geotechnical systems. Conventional X-ray CT systems typically utilize a polychromatic X-ray beam. While providing a high throughput of photons, the use of polychromatic energy can make quantifying material concentrations, densities or composition very difficult or impossible without appropriate standards. Synchrotron X-rays have an extremely small angular divergence, thus permitting spatial resolution that is only limited by the optical components of the system. In addition, the ability to tune to a monochromatic X-ray energy allows better phase contrast by reducing beam hardening and allowing for elemental discrimination. In this work we will show how monochromatic energy can be used to provide high-quality images allowing for phase separation several different porous media systems thus improving our ability to quantify a range of processes and phenomena.

Ham, Kyungmin; Willson, Clinton S. (LSU)

2006-01-31T23:59:59.000Z

228

Muon Muon Collider: Feasibility Study  

SciTech Connect

A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of

Gallardo, J.C.; Palmer, R.B.; /Brookhaven; Tollestrup, A.V.; /Fermilab; Sessler, A.M.; /LBL, Berkeley; Skrinsky, A.N.; /Novosibirsk, IYF; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley

2012-04-05T23:59:59.000Z

229

Radiation dose reduction using a CdZnTe-based computed tomography system: Comparison to flat-panel detectors  

Science Conference Proceedings (OSTI)

Purpose: Although x-ray projection mammography has been very effective in early detection of breast cancer, its utility is reduced in the detection of small lesions that are occult or in dense breasts. One drawback is that the inherent superposition of parenchymal structures makes visualization of small lesions difficult. Breast computed tomography using flat-panel detectors has been developed to address this limitation by producing three-dimensional data while at the same time providing more comfort to the patients by eliminating breast compression. Flat panels are charge integrating detectors and therefore lack energy resolution capability. Recent advances in solid state semiconductor x-ray detector materials and associated electronics allow the investigation of x-ray imaging systems that use a photon counting and energy discriminating detector, which is the subject of this article. Methods: A small field-of-view computed tomography (CT) system that uses CdZnTe (CZT) photon counting detector was compared to one that uses a flat-panel detector for different imaging tasks in breast imaging. The benefits afforded by the CZT detector in the energy weighting modes were investigated. Two types of energy weighting methods were studied: Projection based and image based. Simulation and phantom studies were performed with a 2.5 cm polymethyl methacrylate (PMMA) cylinder filled with iodine and calcium contrast objects. Simulation was also performed on a 10 cm breast specimen. Results: The contrast-to-noise ratio improvements as compared to flat-panel detectors were 1.30 and 1.28 (projection based) and 1.35 and 1.25 (image based) for iodine over PMMA and hydroxylapatite over PMMA, respectively. Corresponding simulation values were 1.81 and 1.48 (projection based) and 1.85 and 1.48 (image based). Dose reductions using the CZT detector were 52.05% and 49.45% for iodine and hydroxyapatite imaging, respectively. Image-based weighting was also found to have the least beam hardening effect. Conclusions: The results showed that a CT system using an energy resolving detector reduces the dose to the patient while maintaining image quality for various breast imaging tasks.

Le, Huy Q.; Ducote, Justin L.; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

2010-03-15T23:59:59.000Z

230

Correlation of Molecular Response as Measured by 18-FDG Positron Emission Tomography With Outcome After Chemoradiotherapy in Patients with Esophageal Carcinoma  

SciTech Connect

Purpose: To determine whether 18-fluorodeoxyglucose positron emission tomography (PET) computed tomography scans predict the pathologic complete response and disease-free and overall survival in patients with esophageal carcinoma undergoing definitive or preoperative chemoradiotherapy. Methods and Materials: The records of patients with esophageal carcinoma presenting for definitive or preoperative treatment and undergoing pre- and post-treatment 18-fluorodeoxyglucose PET-computed tomography scans were retrospectively reviewed. The histologic type, T stage, and nodal status were the variables investigated to determine a relationship with the baseline standardized uptake value (SUV) of the primary tumor at diagnosis. We also attempted to determine whether a relationship exists between the percent decrease in SUV and a pathologic complete response, overall and disease-free survival. Results: A total of 81 patients, 14 women and 67 men, underwent 18-fluorodeoxyglucose PET-computed tomography scanning before treatment and 63 also had post-treatment scans. T stage and tumor location predicted in univariate, but not multivariate, analysis for the initial SUV. Of the patients with a postchemoradiotherapy SUV of <2.5, 66% had tumor in the surgical specimen and 64% of patients had positive lymph nodes at surgery that were not imaged on the postchemoradiotherapy PET scan. A trend existed for post-treatment SUV and the days from radiotherapy to surgery to predict for a pathologic complete response (p = 0.09 and p = 0.08, respectively). The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group (p = 0.01). Conclusions: A correlation was found between the depth of tumor invasion and the baseline SUV. The post-treatment SUV predicted for disease-free survival in the definitive chemoradiotherapy group. Caution should be exercised in using post-treatment PET scans to determine the necessity for surgical resection.

Konski, Andre A. [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)], E-mail: andre.konski@fccc.edu; Cheng, Jonathan D. [Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Goldberg, Melvyn [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Li Tianyu [Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, PA (United States); Maurer, Alan [Department of Nuclear Medicine, Temple University School of Medicine, Philadelphia PA (United States); Yu, Jian Q. [Department of Radiology, Fox Chase Cancer Center, Philadelphia, PA (United States); Haluszka, Oleh [Division of Gastroenterology, Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Scott, Walter [Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Meropol, Neal J.; Cohen, Steven J. [Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Freedman, Gary [Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States); Weiner, Louis M. [Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA (United States)

2007-10-01T23:59:59.000Z

231

An application of Crosswell Tomography using a hydrophone receiver array and airgun source to monitor steam migration in an unconsolidated, heavy-oil sandstone, West Coalinga Field, California  

SciTech Connect

This crosswell tomography field trial demonstrates the viability and cost- reducing benefits of a hydrophone receiver array and airgun source for monitoring steam (heat) migration within an unconsolidated, heavy-oil sandstone. This project represents one of the first applications of hydrophone receivers in such an environment. Data quality from the hydrophone array proved more than adequate for P-wave tomography while costs were reduced dramatically from estimates using a clamped geophone array. Additionally, the resolution provided by the capture of travel-time data from interwell areas offered a distinct advantage over conventional monitoring techniques limited to observation wells. Two crosswell surveys were conducted in the vicinity of a new, infill steam injector. The purpose was to monitor steam migration within an 80-foot thick, sandstone interval by detecting the heat-induced velocity decrease between the first survey, conducted just before steam injection, and the second survey conducted approximately three months later. Difference plots of the two surveys clearly define regions of significant temperature change and contact temperature logs corroborate the zone of peak change. The crosswell tomography data and the inferred steam migration characteristics immediately altered an operational strategy for the drive and were later a factor in the abandonment of continuous steam injection.

Blevens, D.M. (Chevron USA Production Co., Bakersfield, CA (United States)); Fairborn, J.W. (Wellseismic Computing Services, Balboa, CA (United States))

1996-01-01T23:59:59.000Z

232

MUON ACCELERATION  

Science Conference Proceedings (OSTI)

One of the major motivations driving recent interest in FFAGs is their use for the cost-effective acceleration of muons. This paper summarizes the progress in this area that was achieved leading up to and at the FFAG workshop at KEK from July 7-12, 2003. Much of the relevant background and references are also given here, to give a context to the progress we have made.

BERG,S.J.

2003-11-18T23:59:59.000Z

233

2-Deoxy-2-[F-18]fluoro-D-glucose Joint Uptake on Positron Emission Tomography Images: Rheumatoid Arthritis Versus Osteoarthritis  

E-Print Network (OSTI)

Purpose: Previous positron emission tomography (PET) studies have shown increased 2-deoxy-2-[18F]fluoro-D-glucose (FDG) uptake in joints of patients with osteoarthritis (OA) and inflamed joints of patients with rheumatoid arthritis (RA). This study compares FDG uptake in joints of RA and OA patients and FDG-uptake with clinical signs of inflammation. Procedures: FDG-PET scans of hands and wrists were performed in patients with RA and primary OA. PET data were compared with clinical data. Results: 29 % of RA joints and 6 % of OA joints showed elevated FDG-uptake. The level of uptake in PET-positive OA joints was not significantly different from that in RA joints. The majority of PET results of RA joints corresponded with clinical findings. Clinical synovitis was found some OA joints with FDG-uptake. Conclusions: FDG-uptake was observed in the majority of clinically inflamed RA joints and in a few OA joints with no significant difference in uptake level. The latter may be due to secondary synovitis.

E. H. Elzinga; B. A. C. Dijkmans; A. E. Voskuyl

2007-01-01T23:59:59.000Z

234

Role of Positron Emission Tomography in the Treatment of Occult Disease in Head-and-Neck Cancer: A Modeling Approach  

SciTech Connect

Purpose: To determine under what conditions positron emission tomography (PET) imaging will be useful in decisions regarding the use of radiotherapy for the treatment of clinically occult lymph node metastases in head-and-neck cancer. Methods and Materials: A decision model of PET imaging and its downstream effects on radiotherapy outcomes was constructed using an influence diagram. This model included the sensitivity and specificity of PET, as well as the type and stage of the primary tumor. These parameters were varied to determine the optimal strategy for imaging and therapy for different clinical situations. Maximum expected utility was the metric by which different actions were ranked. Results: For primary tumors with a low probability of lymph node metastases, the sensitivity of PET should be maximized, and 50 Gy should be delivered if PET is positive and 0 Gy if negative. As the probability for lymph node metastases increases, PET imaging becomes unnecessary in some situations, and the optimal dose to the lymph nodes increases. The model needed to include the causes of certain health states to predict current clinical practice. Conclusion: The model demonstrated the ability to reproduce expected outcomes for a range of tumors and provided recommendations for different clinical situations. The differences between the optimal policies and current clinical practice are likely due to a disparity between stated clinical decision processes and actual decision making by clinicians.

Phillips, Mark H., E-mail: markp@u.washington.ed [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States); Smith, Wade P. [Department of Veterans Affairs, Albany, NY (United States); Parvathaneni, Upendra; Laramore, George E. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States)

2011-03-15T23:59:59.000Z

235

Permeability of laboratory-formed methane-hydrate-bearing sand: Measurements and observations using x-ray computed tomography  

SciTech Connect

Methane hydrate was formed in two moist sands and a sand/silt mixture under a confining stress in an X-ray-transparent pressure vessel. Three initial water saturations were used to form three different methane-hydrate saturations in each medium. X-ray computed tomography (CT) was used to observe location-specific density changes caused by hydrate formation and flowing water. Gas-permeability measurements in each test for the dry, moist, frozen, and hydrate-bearing states are presented. As expected, the effective permeabilities (intrinsic permeability of the medium multiplied by the relative permeability) of the moist sands decreased with increasing moisture content. In a series of tests on a single sample, the effective permeability typically decreased as the pore space became more filled, in the order of dry, moist, frozen, and hydrate-bearing. In each test, water was flowed through the hydrate-bearing medium and we observed the location-specific changes in water saturation using CT scanning. We compared our data to a number of models, and our relative permeability data compare most favorably with models in which hydrate occupies the pore bodies rather than the pore throats. Inverse modeling (using the data collected from the tests) will be performed to extend the relative permeability measurements.

Kneafsey, T. J.; Seol, Y.; Gupta, A.; Tomutsa, L.

2010-09-15T23:59:59.000Z

236

X-ray computed-tomography observations of water flow through anisotropic methane hydrate-bearing sand  

SciTech Connect

We used X-ray computed tomography (CT) to image and quantify the effect of a heterogeneous sand grain-size distribution on the formation and dissociation of methane hydrate, as well as the effect on water flow through the heterogeneous hydrate-bearing sand. A 28 cm long sand column was packed with several segments having vertical and horizontal layers with sands of different grain-size distributions. During the hydrate formation, water redistribution occurred. Observations of water flow through the hydrate-bearing sands showed that water was imbibed more readily into the fine sand, and that higher hydrate saturation increased water imbibition in the coarse sand due to increased capillary strength. Hydrate dissociation induced by depressurization resulted in different flow patterns with the different grain sizes and hydrate saturations, but the relationships between dissociation rates and the grain sizes could not be identified using the CT images. The formation, presence, and dissociation of hydrate in the pore space dramatically impact water saturation and flow in the system.

Seol, Yongkoo; Kneafsey, Timothy J.

2009-06-01T23:59:59.000Z

237

Quantification of Mediastinal and Hilar Lymph Node Movement Using Four-Dimensional Computed Tomography Scan: Implications for Radiation Treatment Planning  

SciTech Connect

Purpose: To quantitatively describe mediastinal and hilar lymph node movement in patients with lymph node-positive lung cancer. Methods and Materials: Twenty-four patients with lung cancer who underwent four-dimensional computed tomography scanning at Massachusetts General Hospital were included in the study. The maximum extent of superior motion of the superior border was measured, as well as the maximum inferior movement of the inferior border. The average of these two values is defined as the peak-to-peak movement. This process was repeated for mediolateral (ML) and anterior-posterior (AP) movement. Linear regression was used to determine lymph node characteristics associated with peak-to-peak movement. Various uniform expansions were investigated to determine the expansion margins necessary to ensure complete internal target volume (ITV) coverage. Results: The mean peak-to-peak displacements of paratracheal lymph nodes were 4 mm (craniocaudal [CC]), 2 mm (ML), and 2 mm (AP). For subcarinal lymph nodes, the mean peak-to-peak movements were 6 mm (CC), 4 mm (ML), and 2 mm (AP). The mean peak-to-peak displacements of hilar lymph nodes were 7 mm (CC), 1 mm (ML), and 4 mm (AP). On multivariate analysis, lymph node station and lymph node size were significantly related to peak-to-peak movement. Expansions of 8 mm for paratracheal nodes and 13 mm for subcarinal and hilar nodes would have been necessary to cover the ITV of 95% of these nodal masses. Conclusions: Subcarinal and hilar lymph nodes may move substantially throughout the respiratory cycle. In the absence of patient-specific information on nodal motion, expansions of at least 8 mm, 13 mm, and 13 mm should be considered to cover the ITV of paratracheal, subcarinal, and hilar lymph nodes, respectively.

Sher, David J.; Wolfgang, John A.; Niemierko, Andrzej [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States); Choi, Noah C. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA (United States)], E-mail: nchoi@partners.org

2007-12-01T23:59:59.000Z

238

Implications of Respiratory Motion as Measured by Four-Dimensional Computed Tomography for Radiation Treatment Planning of Esophageal Cancer  

Science Conference Proceedings (OSTI)

Purpose: To evaluate the respiratory motion of primary esophageal cancers and pathologic celiac-region lymph nodes using time-resolved four-dimensional computed tomography (4D CT). Methods and Materials: Respiration-synchronized 4D CT scans were obtained to quantify the motion of primary tumors located in the proximal, mid-, or distal thoracic esophagus, as well as any involved celiac-region lymph nodes. Respiratory motion was measured in the superior-inferior (SI), anterior-posterior (AP), and left-right (LR) directions and was analyzed for correlation with anatomic location. Recommended margin expansions were determined for both primary and nodal targets. Results: Thirty patients underwent 4D CT scans at Massachusetts General Hospital for planned curative treatment of esophageal cancer. Measurements of respiratory tumor motion were obtained for 1 proximal, 4 mid-, and 25 distal esophageal tumors, as well as 12 involved celiac-region lymph nodes. The mean (SD) peak-to-peak displacements of all primary tumors in the SI, AP, and LR dimensions were 0.80 (0.45) cm, 0.28 (0.20) cm, and 0.22 (0.23) cm, respectively. Distal tumors were found to have significantly greater SI and AP motion than proximal or mid-esophageal tumors. The mean (SD) SI, AP, and LR peak-to-peak displacements of the celiac-region lymph nodes were 0.92 (0.56) cm, 0.46 (0.27) cm, and 0.19 (0.26) cm, respectively. Conclusions: Margins of 1.5 cm SI, 0.75 cm AP, and 0.75 cm LR would account for respiratory tumor motion of >95% of esophageal primary tumors in the dataset. All celiac-region lymph nodes would be adequately covered with SI, AP, and LR margins of 2.25 cm, 1.0 cm, and 0.75 cm, respectively.

Patel, Abhijit A.; Wolfgang, John A.; Niemierko, Andrzej; Hong, Theodore S.; Yock, Torunn [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Choi, Noah C. [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States)], E-mail: nchoi@partners.org

2009-05-01T23:59:59.000Z

239

Coronary artery wall imaging in mice using osmium tetroxide and micro-computed tomography (micro-CT)  

SciTech Connect

The high spatial resolution of micro-computed tomography (micro-CT) is ideal for 3D imaging of coronary arteries in intact mouse heart specimens. Previously, micro-CT of mouse heart specimens utilized intravascular contrast agents that hardened within the vessel lumen and allowed a vascular cast to be made. However, for mouse coronary artery disease models, it is highly desirable to image coronary artery walls and highlight plaques. For this purpose, we describe an ex vivo contrast-enhanced micro-CT imaging technique based on tissue staining with osmium tetroxide (OsO{sub 4}) solution. As a tissue-staining contrast agent, OsO{sub 4} is retained in the vessel wall and surrounding tissue during the fixation process and cleared from the vessel lumens. Its high X-ray attenuation makes the artery wall visible in CT. Additionally, since OsO{sub 4} preferentially binds to lipids, it highlights lipid deposition in the artery wall. We performed micro-CT of heart specimens of 5- to 25-week-old C57BL/6 wild-type mice and 5- to 13-week-old apolipoprotein E knockout (apoE{sup -/-}) mice at 10 {mu}m resolution. The results show that walls of coronary arteries as small as 45 {mu}m in diameter are visible using a table-top micro-CT scanner. Similar image clarity was achieved with 1/2000th the scan time using a synchrotron CT scanner. In 13-week-old apoE mice, lipid-rich plaques are visible in the aorta. Our study shows that the combination of OsO{sub 4} and micro-CT permits the visualization of the coronary artery wall in intact mouse hearts.

Pai, Vinay M.; Kozlowski, Megan; Donahue, Danielle; Miller, Elishiah; Xiao, Xianghui; Chen, Marcus Y.; Yu, Zu-Xi; Connelly, Patricia; Jeffries, Kenneth; Wen, Han (NIH)

2012-05-10T23:59:59.000Z

240

Crust and upper mantle P wave velocity structure beneath Valles caldera, New Mexico: Results from the Jemez teleseismic tomography experiment  

Science Conference Proceedings (OSTI)

New results are presented from the teleseismic component of the Jemez Tomography Experiment conducted across Valles caldera in northern New Mexico. We invert 4872 relative {ital P} wave arrival times recorded on 50 portable stations to determine velocity structure to depths of 40 km. The three principle features of our model for Valles caldera are: (1) near-surface low velocities of {minus}17{percent} beneath the Toledo embayment and the Valle Grande, (2) midcrustal low velocities of {minus}23{percent} in an ellipsoidal volume underneath the northwest quadrant of the caldera, and (3) a broad zone of low velocities ({minus}15{percent}) in the lower crust or upper mantle. Crust shallower than 20 km is generally fast to the northwest of the caldera and slow to the southeast. Near-surface low velocities are interpreted as thick deposits of Bandelier tuff and postcaldera volcaniclastic rocks. Lateral variation in the thickness of these deposits supports increased caldera collapse to the southeast, beneath the Valle Grande. We interpret the midcrustal low-velocity zone to contain a minimum melt fraction of 10{percent}. While we cannot rule out the possibility that this zone is the remnant 1.2 Ma Bandelier magma chamber, the eruption history and geochemistry of the volcanic rocks erupted in Valles caldera following the Bandelier tuff make it more likely that magma results from a new pulse of intrusion, indicating that melt flux into the upper crust beneath Valles caldera continues. The low-velocity zone near the crust-mantle boundary is consistent with either partial melt in the lower crust or mafic rocks without partial melt in the upper mantle. In either case, this low-velocity anomaly indicates that underplating by mantle-derived melts has occurred. {copyright} 1998 American Geophysical Union

Steck, Lee K.; Fehler, Michael C.; Roberts, Peter M.; Baldridge, W. Scott; Stafford, Darrik G. [Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico (United States); Lutter, William J.; Sessions, Robert [Department of Geology and Geophysics, University of Wisconsin-Madison (United States)

1998-10-01T23:59:59.000Z

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241

Sub-millimeter nuclear medical imaging with reduced dose application in positron emission tomography using beta-gamma coincidences  

E-Print Network (OSTI)

Positron emission tomography (PET) permits a functional understanding of the underlying causes of many diseases. Modern whole-body PET systems reach a spatial resolution of 2-6 mm (FWHM). A limitation of this technique occurs from the thermalization and diffusion of the positron before its annihilation, typically within the mm range. We present a nuclear medical imaging technique, able to reach sub-millimeter spatial resolution in 3 dimensions with a reduced effective dose application compared to conventional PET. This 'gamma-PET' technique draws on specific medical isotopes, simultaneously emitting an additional photon accompanying the beta^+ decay. Exploiting the triple coincidence between the positron annihilation and the third photon, it is possible to separate the reconstructed 'true' events from background. In order to characterize the potential of this technique, MC simulations and image reconstructions have been performed. The achievable spatial resolution has been found to reach ca. 0.4 mm (FWHM) in each direction for the visualization of a 22Na point source. Starting with a source activity of only 1.48 MBq for 89Zr, corresponding to ca. 130 - 270 times less compared to a conventional PET examination using 18F-FDG, about 40 intersections (sufficient for a reliable image reconstruction of a point source) can be identified after a typical examination time of 900 seconds. This results in a strongly reduced effective dose of, e.g., 0.785 mSv for 89Zr-cmAb-U36, compared to the applied effective dose in a typical human PET examination with 18F-FDG of about 7.5 mSv. Increasing the applied effective dose to 7.5 mSv, the examination time will be reduced to 94 s for only 14.2 MBq of 89Zr-cmAb-U36. The reduced effective dose, or, the reduced examination time, surpass the performance of a conventional PET device by more than one order of magnitude.

C. Lang; D. Habs; K. Parodi; P. G. Thirolf

2013-05-18T23:59:59.000Z

242

An adaptive approach to metal artifact reduction in helical computed tomography for radiation therapy treatment planning: Experimental and clinical studies  

SciTech Connect

Purpose: In this article, an approach to metal artifact reduction is proposed that is practical for clinical use in radiation therapy. It is based on a new interpolation scheme of the projections associated with metal implants in helical computed tomography (CT) scanners. Methods and Materials: A three-step approach was developed consisting of an automatic algorithm for metal implant detection, a correction algorithm for helical projections, and a new, efficient algorithm for projection interpolation. The modified raw projection data are transferred back to the CT scanner device where CT slices are regenerated using the built-in reconstruction operator. The algorithm was tested on a CT calibration phantom in which the density of inserted objects are known and on clinical prostate cases with two hip prostheses. The results are evaluated using the CT number and shape of the objects. Results: The validations on a CT calibration phantom with various inserts of known densities show that the algorithm improved the overall image quality by restoring the shape and the representative CT number of the objects in the image. For the clinical hip replacement cases, a large fraction of the bladder, rectum, and prostate that were not visible on the original CT slices were recovered using the algorithm. Precise contouring of the target volume was thus feasible. Without this enhancement, physicians would have drawn bigger margins to be sure to include the target and, at the same time, could have prescribed a lower dose to keep the same level of normal tissue toxicity. Conclusions: In both phantom experiment and patient studies, the algorithm resulted in significant artifact reduction with increases in the reliability of planning procedure for the case of metallic hip prostheses. This algorithm is now clinically used as a preprocessing before treatment planning for metal artifact reduction.

Yazdia, Mehran [Departement de radio-onoclogie and Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec (Canada); Gingras, Luc [Departement de radio-onoclogie and Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec (Canada); Departement de Physique, Genie Physique et d' Optique, Universite Laval, Quebec City, Quebec (Canada); Beaulieu, Luc [Departement de radio-onoclogie and Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec (Canada) and Departement de Physique, Genie Physique et d' Optique, Universite Laval, Quebec City, Quebec (Canada)]. E-mail: beaulieu@phy.ulaval.ca

2005-07-15T23:59:59.000Z

243

Design of intergrated radiation detectors with a-Si photodiodes on ceramic scintillators for use in x-ray computed tomography  

Science Conference Proceedings (OSTI)

An integrated radiation detector with a-Si photodiodes on ceramic scintillators is designed for use in x-ray computed tomography. The output signal is estimated using Monte Carlo simulation. Results show that this detector has higher sensitivity than a c-Si photodiode/scintillator detector when a transparent layer between the scintillator and the thin film semiconductor is optimized. The noise characteristic is also considered when an integrated detector is coupled with an operational amplifier. Good agreement is shown between predicted and measured parameters.

Takahashi, T.; Itoh, H.; Shimada, T.; Takeuchi, H. (Central Research Lab., Hitachi, Ltd., P.O. Box 2, Kokubunji, Tokyo (JP))

1990-06-01T23:59:59.000Z

244

Intensity Modulated Radiation Therapy Dose Painting for Localized Prostate Cancer Using {sup 11}C-choline Positron Emission Tomography Scans  

Science Conference Proceedings (OSTI)

Purpose: To demonstrate the technical feasibility of intensity modulated radiation therapy (IMRT) dose painting using {sup 11}C-choline positron emission tomography PET scans in patients with localized prostate cancer. Methods and Materials: This was an RT planning study of 8 patients with prostate cancer who had {sup 11}C-choline PET scans prior to radical prostatectomy. Two contours were semiautomatically generated on the basis of the PET scans for each patient: 60% and 70% of the maximum standardized uptake values (SUV{sub 60%} and SUV{sub 70%}). Three IMRT plans were generated for each patient: PLAN{sub 78}, which consisted of whole-prostate radiation therapy to 78 Gy; PLAN{sub 78-90}, which consisted of whole-prostate RT to 78 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy; and PLAN{sub 72-90}, which consisted of whole-prostate RT to 72 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy. The feasibility of these plans was judged by their ability to reach prescription doses while adhering to published dose constraints. Tumor control probabilities based on PET scan-defined volumes (TCP{sub PET}) and on prostatectomy-defined volumes (TCP{sub path}), and rectal normal tissue complication probabilities (NTCP) were compared between the plans. Results: All plans for all patients reached prescription doses while adhering to dose constraints. TCP{sub PET} values for PLAN{sub 78}, PLAN{sub 78-90}, and PLAN{sub 72-90} were 65%, 97%, and 96%, respectively. TCP{sub path} values were 71%, 97%, and 89%, respectively. Both PLAN{sub 78-90} and PLAN{sub 72-90} had significantly higher TCP{sub PET} (P=.002 and .001) and TCP{sub path} (P<.001 and .014) values than PLAN{sub 78}. PLAN{sub 78-90} and PLAN{sub 72-90} were not significantly different in terms of TCP{sub PET} or TCP{sub path}. There were no significant differences in rectal NTCPs between the 3 plans. Conclusions: IMRT dose painting for localized prostate cancer using {sup 11}C-choline PET scans is technically feasible. Dose painting results in higher TCPs without higher NTCPs.

Chang, Joe H. [Radiation Oncology Centre, Austin Health, Victoria (Australia) [Radiation Oncology Centre, Austin Health, Victoria (Australia); University of Melbourne, Victoria (Australia); Lim Joon, Daryl [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Lee, Sze Ting [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Centre for PET, Austin Health, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Gong, Sylvia J. [Centre for PET, Austin Health, Victoria (Australia)] [Centre for PET, Austin Health, Victoria (Australia); Anderson, Nigel J. [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Scott, Andrew M. [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Centre for PET, Austin Health, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Davis, Ian D. [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Clouston, David [Focus Pathology, Victoria (Australia)] [Focus Pathology, Victoria (Australia); Bolton, Damien [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Department of Urology, Austin Health, Victoria (Australia); Hamilton, Christopher S. [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Khoo, Vincent, E-mail: vincent.khoo@rmh.nhs.uk [Radiation Oncology Centre, Austin Health, Victoria (Australia) [Radiation Oncology Centre, Austin Health, Victoria (Australia); University of Melbourne, Victoria (Australia); Department of Clinical Oncology, Royal Marsden Hospital and Institute of Cancer Research, London (United Kingdom)

2012-08-01T23:59:59.000Z

245

Fluorescence enhanced optical tomography on breast phantoms with measurements using a gain modulated intensified CCD imaging system  

E-Print Network (OSTI)

Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in-vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. However, prior to the administration of unproven contrast agents, the benefits of fluorescence-enhanced optical imaging must be assessed in feasibility phantom studies. A novel intensified charge-coupled device (ICCD) imaging system has been developed to perform 3-D fluorescence tomographic imaging in the frequency-domain using near-infrared contrast agents. This study is unique since it (i) employs a large tissue-mimicking phantom (~1087 cc), which is shaped and sized to resemble a female breast and part of the extended chest wall region, and (ii) enables rapid data acquisition in the frequency-domain by using a gain-modulated ICCD camera. Diagnostic 3-D fluorescence-enhanced optical tomography is demonstrated using 0.5-1 cc single and multiple targets contrasted from their surrounding by ??M concentrations of Indocyanine green (ICG) in the breast-shaped phantom (10 cm diameter), under varying conditions of target-to-background absorption contrast ratios (1:0 and 100:1) and target depths (up to 3 cm deep). Boundary surface fluorescence measurements of referenced amplitude and phase shift were used along with the coupled diffusion equation of light propagation in order to perform 3-D image reconstructions using the approximate extended Kalman filter (AEKF) algorithm, and hence differentiate the target from the background based on fluorescent optical contrast. Detection of single and multiple targets is demonstrated under various conditions of target depths (up to 2 cm deep), absorption optical contrast ratio (1:0 and 100:1), target volumes (0.5-1 cc), and multiple targets (up to three 0.5 cc targets). The feasibility of 3-D image reconstructions from simultaneous multiple point excitation sources are presented. Preliminary lifetime imaging studies with 1:2 and 2:1 optical contrast in fluorescence lifetime of the contrast agents is also demonstrated. The specificity of the optical imager is further assessed from homogeneous phantom studies containing no fluorescently contrasted targets. While nuclear imaging currently provides clinical diagnostic opportunities using radioactive tracers, molecular targeting of tumors using non-ionizing NIR contrast agents tomographically imaged using the frequency-domain ICCD imaging system could possibly become a new method of diagnostic imaging.

Godavarty, Anuradha

2003-12-01T23:59:59.000Z

246

Outcomes of Positron Emission Tomography-Staged Clinical N3 Breast Cancer Treated With Neoadjuvant Chemotherapy, Surgery, and Radiotherapy  

SciTech Connect

Purpose: To evaluate the treatment outcome and efficacy of regional lymph node irradiation after neoadjuvant chemotherapy (NCT) and surgery in positron emission tomography (PET)-positive clinical N3 (cN3) breast cancer patients. Methods and Materials: A total of 55 patients with ipsilateral infraclavicular (ICL), internal mammary (IMN), or supraclavicular (SCL) lymph node involvement in the absence of distant metastases, as revealed by an initial PET scan, were retrospectively analyzed. The clinical nodal stage at diagnosis (2002 AJCC) was cN3a in 14 patients (26%), cN3b in 12 patients (22%), and cN3c in 29 patients (53%). All patients were treated with NCT, followed by mastectomy or breast-conserving surgery and subsequent radiotherapy (RT) with curative intent. Results: At the median follow-up of 38 months (range, 9-80 months), 20 patients (36%) had developed treatment failures, including distant metastases either alone or combined with locoregional recurrences that included one ipsilateral breast recurrence (IBR), six regional failures (RF), and one case of combined IBR and RF. Only 3 patients (5.5%) exhibited treatment failure at the initial PET-positive clinical N3 lymph node. The 5-year locoregional relapse-free survival, disease-free survival (DFS), and overall survival rates were 80%, 60%, and 79%, respectively. RT delivered to PET-positive IMN regions in cN3b patients and at higher doses ({>=}55 Gy) to SCL regions in cN3c patients was not associated with improved 5-year IMN/SCL relapse-free survival or DFS. Conclusion: NCT followed by surgery and RT, including the regional lymph nodes, resulted in excellent locoregional control for patients with PET-positive cN3 breast cancer. The primary treatment failure in this group was due to distant metastasis rather than RF. Neither higher-dose RT directed at PET-positive SCL nodes nor coverage of PET-positive IMN nodes was associated with additional gains in locoregional control or DFS.

Park, Hae Jin [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Shin, Kyung Hwan, E-mail: radiat@ncc.re.kr [Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Cho, Kwan Ho [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Park, In Hae; Lee, Keun Seok; Ro, Jungsil; Jung, So-Youn; Lee, Seeyoun; Kim, Seok Won; Kang, Han-Sung [Center for Breast Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Chie, Eui Kyu; Ha, Sung Whan [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2011-12-01T23:59:59.000Z

247

Artifacts in Conventional Computed Tomography (CT) and Free Breathing Four-Dimensional CT Induce Uncertainty in Gross Tumor Volume Determination  

Science Conference Proceedings (OSTI)

Purpose: Artifacts impacting the imaged tumor volume can be seen in conventional three-dimensional CT (3DCT) scans for planning of lung cancer radiotherapy but can be reduced with the use of respiration-correlated imaging, i.e., 4DCT or breathhold CT (BHCT) scans. The aim of this study was to compare delineated gross tumor volume (GTV) sizes in 3DCT, 4DCT, and BHCT scans of patients with lung tumors. Methods and Materials: A total of 36 patients with 46 tumors referred for stereotactic radiotherapy of lung tumors were included. All patients underwent positron emission tomography (PET)/CT, 4DCT, and BHCT scans. GTVs in all CT scans of individual patients were delineated during one session by a single physician to minimize systematic delineation uncertainty. The GTV size from the BHCT was considered the closest to true tumor volume and was chosen as the reference. The reference GTV size was compared to GTV sizes in 3DCT, at midventilation (MidV), at end-inspiration (Insp), and at end-expiration (Exp) bins from the 4DCT scan. Results: The median BHCT GTV size was 4.9 cm{sup 3} (0.1-53.3 cm{sup 3}). Median deviation between 3DCT and BHCT GTV size was 0.3 cm{sup 3} (-3.3 to 30.0 cm{sup 3}), between MidV and BHCT size was 0.2 cm{sup 3} (-5.7 to 19.7 cm{sup 3}), between Insp and BHCT size was 0.3 cm{sup 3} (-4.7 to 24.8 cm{sup 3}), and between Exp and BHCT size was 0.3 cm{sup 3} (-4.8 to 25.5 cm{sup 3}). The 3DCT, MidV, Insp, and Exp median GTV sizes were all significantly larger than the BHCT median GTV size. Conclusions: In the present study, the choice of CT method significantly influenced the delineated GTV size, on average, leading to an increase in GTV size compared to the reference BHCT. The uncertainty caused by artifacts is estimated to be in the same magnitude as delineation uncertainty and should be considered in the design of margins for radiotherapy.

Fredberg Persson, Gitte, E-mail: gitte.persson@rh.regionh.dk [Department of Radiation Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen (Denmark); Nygaard, Ditte Eklund; Munch af Rosenschoeld, Per; Richter Vogelius, Ivan; Josipovic, Mirjana [Department of Radiation Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen (Denmark); Specht, Lena [Department of Radiation Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen (Denmark); Faculty of Health Sciences, University of Copenhagen, Copenhagen (Denmark); Korreman, Stine Sofia [Department of Radiation Oncology, Copenhagen University Hospital, Rigshospitalet, Copenhagen (Denmark); Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin (United States); Niels Bohr Institute, Faculty of Sciences, University of Copenhagen, Copenhagen (Denmark)

2011-08-01T23:59:59.000Z

248

Neutron Tomography and Space  

E-Print Network (OSTI)

Propulsion Laboratory (JPL), uses a small Maxom motor on applications for manipulators in some of their space

Egbert, Hal; Walker, Ronald; Flocchini, R.

2007-01-01T23:59:59.000Z

249

Electron tomography of defects  

E-Print Network (OSTI)

semiconductor specimens with sufficiently low amounts of damage as to give some area with defect structure typical of the material before sample preparation. A similar study in brass [18] (more ductile, with more damage expected) found the maximum depth... for these samples [19]. As seen by comparing silicon and brass, subjecting a ductile material to abrasion causes much deeper disruption than in a brittle material, as energy is diverted to plastic deformation. 1.3.2 Non-mechanical shaping methods Spark cutting may...

Sharp, Joanne

2010-10-12T23:59:59.000Z

250

NIST: NIF - Neutron Tomography  

Science Conference Proceedings (OSTI)

... can be made. The technique is similar to CAT scans, and is based on the Filtered Back Projection Algorithm. The NIF has ...

251

Investigating the correlation between residual nonwetting phase liquids and pore-scale geometry and topology using synchrotron x-ray tomography  

Science Conference Proceedings (OSTI)

The entrapment of nonwetting phase fluids in unconsolidated porous media systems is strongly dependent on the pore-scale geometry and topology. Synchrotron X-ray tomography allows us to nondestructively obtain high-resolution (on the order of 1-10 micron), three-dimensional images of multiphase porous media systems. Over the past year, a number of multiphase porous media systems have been imaged using the synchrotron X-ray tomography station at the GeoSoilEnviroCARS beamline at the Advanced Photon Source. For each of these systems, we are able to: (1) obtain the physically-representative network structure of the void space including the pore body and throat distribution, coordination number, and aspect ratio; (2) characterize the individual nonwetting phase blobs/ganglia (e.g., volume, sphericity, orientation, surface area); and (3) correlate the porous media and fluid properties. The images, data, and network structure obtained from these experiments provide us with a better understanding of the processes and phenomena associated with the entrapment of nonwetting phase fluids. Results from these experiments will also be extremely useful for researchers interested in interphase mass transfer and those utilizing network models to study the flow of multiphase fluids in porous media systems.

Willson, C.S.; Ham, K.; Thompson, K.A. (LSU)

2005-02-02T23:59:59.000Z

252

A prospective evaluation of the impact of 18-F-fluoro-deoxy-D-glucose positron emission tomography staging on survival for patients with locally advanced esophageal cancer  

SciTech Connect

Purpose: To determine the impact of 18-F-fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the staging and prognosis of patients with locally advanced esophageal cancer (LAEC). Methods and Materials: Between January 2000 and October 2004, all patients with LAEC evaluated in the Department of Radiation Oncology were considered for enrollment into a Phase II trial of preoperative chemoradiation. Entry required a staging whole-body FDG-PET scan. Results: One hundred ten consecutive patients were evaluated; 38 were ineligible for reasons including treatment elsewhere, prior malignancy, or refusal of treatment. After conventional staging (clinical examination, endoscopic ultrasound, and chest/abdominal computerized tomography), 33 patients were ineligible because of metastatic disease or poor performance status. Of the remaining 39 patients, 23 were confirmed to have LAEC after FDG-PET staging and were treated in the Phase II trial (Cohort I). Sixteen patients, however, had FDG-PET findings consistent with occult metastatic disease and were deemed ineligible for the trial but were treated with curative intent (Cohort II). The 2-year survival rate for the 23 patients in Cohort I was 64%, compared with 17% (p = 0.003) for patients in Cohort II (FDG-PET positive). Conclusions: More than one-third of patients determined to have LAEC with conventional staging were upstaged with the use of FDG-PET. Despite comparable therapy, upstaging with FDG-PET predicts poor 2-year survival.

Blackstock, A. William [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston Salem, NC (United States)]. E-mail: ablackst@wfubmc.edu; Farmer, Michael R. [Department of Radiation Oncology, Wake Forest University School of Medicine, Winston Salem, NC (United States); Lovato, James [Department of Public Health Sciences, Wake Forest University School of Medicine, Winston Salem, NC (United States); Mishra, Girish [Division of Gastroenterology, Wake Forest University School of Medicine, Winston Salem, NC (United States); Melin, Susan A. [Division of Medical Oncology, Wake Forest University School of Medicine, Winston Salem, NC (United States); Oaks, Timothy [Department of Cardiothoracic Surgery, Wake Forest University School of Medicine, Winston Salem, NC (United States); Aklilu, Mabea [Division of Medical Oncology, Wake Forest University School of Medicine, Winston Salem, NC (United States); Clark, Paige B. [Division of Nuclear Medicine, Wake Forest University School of Medicine, Winston Salem, NC (United States); Levine, Edward A. [Department of Surgery, Wake Forest University School of Medicine, Winston Salem, NC (United States)

2006-02-01T23:59:59.000Z

253

Apparatus and method for preparing oxygen-15 labeled water H.sub.2 [.sup.15 O] in an injectable form for use in positron emission tomography  

DOE Patents (OSTI)

A handling and processing apparatus for preparing Oxygen-15 labeled water (H.sub.2 [.sup.15 O]) in injectable form for use in Positron Emission Tomography from preferably H.sub.2 [.sup.15 O] produced by irradiating a flowing gas target of nitrogen and hydrogen. The apparatus includes a collector for receiving and directing a gas containing H.sub.2 [.sup.15 O] gas and impurities, mainly ammonia (NH.sub.3) gas into sterile water to trap the H.sub.2 [.sup.15 O] and form ammonium (NH.sub.4.sup.+) in the sterile water. A device for displacing the sterile water containing H.sub.2 [.sup.15 O] and NH.sub.4.sup.+ through a cation resin removes NH.sub.4.sup.+ from the sterile water. A device for combining the sterile water containing H.sub.2 [.sup.15 O] with a saline solution produces an injectable solution. Preferably, the apparatus includes a device for delivering the solution to a syringe for injection into a patient. Also, disclosed is a method for preparing H.sub.2 [.sup.15 O] in injectable form for use in Positron Emission Tomography in which the method neither requires isotopic exchange reaction nor application of high temperature.

Ferrieri, Richard A. (Patchogue, NY); Schlyer, David J. (Bellport, NY); Alexoff, David (Westhampton, NY)

1996-01-09T23:59:59.000Z

254

Muon Collider History  

NLE Websites -- All DOE Office Websites (Extended Search)

Colliders: A Brief History Below is a brief potted history of the muon collider concept. Click here for a one transparency summary. The muon collider concept is an idea dating back...

255

Neutrino Physics at a Muon Collider  

NLE Websites -- All DOE Office Websites (Extended Search)

Physics at a Muon Collider The intense muon beams needed for high luminosity muon colliders produce intense beams of neutrinos. Dedicated muon storage rings with long straight...

256

Computerized axial tomography: technology and equipment. January, 1977-May, 1981 (Citations from the International Information Service for the Physics and Engineering Communities data base). Report for January 1977-May 1981  

SciTech Connect

This retrospective bibliography contains citations concerning many recent developments in the instrumentation, technology, and application of computerized axial tomography (CAT). Production model CAT scanners are compared and evaluated for noise, spatial resolution, axial position sensitivity, artefact and dose. Research and development on new scanners are considered. (Contains 71 citations fully indexed and including a title list.)

1981-05-01T23:59:59.000Z

257

A Field Proof-of-Concept of Aquifer Imaging Using 3-D Transient Hydraulic Tomography with Modular, Temporarily-Emplaced Equipment  

SciTech Connect

Hydraulic tomography is a field scale aquifer characterization method capable of estimating 3-D heterogeneous parameter distributions, and is directly sensitive to hydraulic conductivity (K), thus providing a useful data source for improving flow and transport models. We present results from a proof-of-concept field and modeling study in which we apply 3-D transient hydraulic tomography (3DTHT) to the relatively high-K and moderately heterogeneous unconfined aquifer at the Boise Hydrogeophysical Research Site. Short-duration (20 min) partially penetrating pumping tests, for which observed responses do not reach steady state, are used as the aquifer stimulation. To collect field data, we utilize a system of temporarily emplaced packer equipment to isolate multiple discrete intervals in boreholes. To analyze the data, we utilize MODFLOW combined with geostatistical inversion code based on the quasilinear approach of Kitanidis (1995). This combination of practical software allows inversion of large datasets (>250 drawdown curves, and almost 1000 individual data points) and estimation of K at >100,000 locations; reasonable runtimes are obtained using a single multicore computer with 12 GB of RAM. The K heterogeneity results from 3DTHT are cross-validated against K characterization from a large set of partially penetrating slug tests, and found to be quite consistent. The use of portable, modular equipment for field implementation means that 3DTHT data collection can be performed (including mobilization/demobilization) within a matter of days. Likewise, use of a practical, efficient and scalable numerical modeling and inversion strategy means that computational effort is drastically reduced, such that 3-D aquifer property distributions can be estimated quickly.

Cardiff, Michael A.; Barrash, Warren; Kitanidis, P. K.

2012-05-19T23:59:59.000Z

258

muon Collider Notes  

NLE Websites -- All DOE Office Websites (Extended Search)

Muon Collider Notes Muon Collider Notes MC-001 D. Neuffer, "Colliding Muon Beams at 90 GeV" Fermilab Note FN-319, July 1979. MC-002 D. Neuffer, "Principles and Applications of Muon Cooling" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 481, 1983. MC-003 V.V. Parkhomchuk and A.N. Skrinsky, "Ionization Cooling: Physics and Applications" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 485, 1983. MC-004 E.A. Perevedentsev and A.N. Skrinsky, "On the Proton Klystron" Proc. of the 12th International Conf. on High-Energy Accelerators, p. 508, 1983. MC-005 D. Neuffer, "Principles and Applications of Muon Cooling" Particle Accelerators, Vol. 14, p. 75, 1983. MC-006 D. Neuffer, "Multi-TeV Muon Colliders" Proc. of the Advanced

259

Papers on Muon Colliders  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnets for Muon Collider and Neutrino Storage Ring Magnets for Muon Collider and Neutrino Storage Ring (and Open Midplane Dipole for LARP): R. Gupta, et al., "High Field HTS Solenoid for a Muon Collider – Demonstrations, Challenges and Strategies, MT23, July 2013", presented at MT23, (talk) R. Weggel et al., "Open Midplane Dipoles for Muon Collider", 2011 Particle Accelerator Conference, New York (POSTER).. R. Gupta, M. Anerella, A. Ghosh, H. Kirk, R. Palmer, S. Plate, W. Sampson, Y. Shiroyanagi, P. Wanderer, B. Brandt, D. Cline, A. Garren, J. Kolonko, R. Scanlan, R. Weggel, "High field HTS R&D solenoid for muon collider", 2010 Applied Superconductivity Conference, Washington, DC, August 2010 >> Y. Shiroyanagi, W. Sampson, A. Ghosh, R. Gupta, "The Construction and

260

Muon Collider Progress: Accelerators  

SciTech Connect

A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

Zisman, Michael S.

2011-09-10T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Links to Muon Collider Related Web Pages  

NLE Websites -- All DOE Office Websites (Extended Search)

Muon Collider related web pages: Muon Collider Feasibility Study ... Fermilab Page MUCOOL Collaboration: Ionization Cooling R&D Snowmass 1996 Feasibility Study Book Brookhaven Muon...

262

ATLAS Muon Detector Commissioning  

E-Print Network (OSTI)

The ATLAS muon spectrometer consists of several major components: Monitored Drift Tubes (MDTs) for precision measurements in the bending plane of the muons, supplemented by Cathode Strip Chambers (CSC) in the high eta region; Resistive Plate Chambers (RPCs) and Thin Gap Chambers (TGCs) for trigger and second coordinate measurement in the barrel and endcap regions, respectively; an optical alignment system to track the relative positions of all chambers; and, finally, the world's largest air-core magnetic toroid system. We will describe the status and commissioning of the muon system with cosmic rays and plans for commissioning with early beams.

E. Diehl; for the ATLAS muon collaboration

2009-10-15T23:59:59.000Z

263

[F-18]-fluorodeoxyglucose positron emission tomography for targeting radiation dose escalation for patients with glioblastoma multiforme: Clinical outcomes and patterns of failure  

SciTech Connect

Purpose: [F-18]-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging for brain tumors has been shown to identify areas of active disease. Radiation dose escalation in the treatment of glioblastoma multiforme may lead to improved disease control. Based on these premises, we initiated a prospective study of FDG-PET for the treatment planning of radiation dose escalation for the treatment of glioblastoma multiforme. Methods and Materials: Forty patients were enrolled. Patients were treated with standard conformal fractionated radiotherapy with volumes defined by MRI imaging. When patients reached a dose of 45-50.4 Gy, they underwent FDG-PET imaging for boost target delineation, for an additional 20 Gy (2 Gy per fraction) to a total dose of 79.4 Gy (n = 30). Results: The estimated 1-year and 2-year overall survival (OS) for the entire group was 70% and 17%, respectively, with a median overall survival of 70 weeks. The estimated 1-year and 2-year progression-free survival (PFS) was 18% and 3%, respectively, with a median of 24 weeks. No significant improvements in OS or PFS were observed for the study group in comparison to institutional historical controls. Conclusions: Radiation dose escalation to 79.4 Gy based on FDG-PET imaging demonstrated no improvement in OS or PFS. This study establishes the feasibility of integrating PET metabolic imaging into radiotherapy treatment planning.

Douglas, James G. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States) and Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States)]. E-mail: drjay@u.washington.edu; Stelzer, Keith J. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States); Celilo Radiation Therapy, Mid-Columbia Medical Center, The Dalles, OR (United States); Mankoff, David A. [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Tralins, Kevin S. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States); Krohn, Kenneth A. [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Muzi, Mark [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Silbergeld, Daniel L. [Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States); Rostomily, Robert C. [Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States); Scharnhorst, Jeffrey B.S. [Department of Neurology, University of Washington Medical Center, Seattle, WA (United States); Spence, Alexander M. [Department of Neurology, University of Washington Medical Center, Seattle, WA (United States)

2006-03-01T23:59:59.000Z

264

Fermilab | Muon Collider | How Does a Muon Collider Work?  

NLE Websites -- All DOE Office Websites (Extended Search)

A muon collider complex would comprise several machines and many different A muon collider complex would comprise several machines and many different components. Scientists across the world are developing and testing them. View full graphic How Does a Muon Collider Work? A muon collider complex would comprise several machines and many different components. Scientists across the world are developing and testing them. Proton accelerator To create lots of muons, scientists use a high-intensity proton accelerator that steers protons into a target. The collisions create short-lived particles called pions. Within 50 meters the pions decay into muons and neutral particles called neutrinos. The muons have an energy of about 200 MeV. Capture cavities Magnets guide the muons into and through a set of radiofrequency cavities. The electric field inside the cavities increases the energy of slow muons

265

The LHCb Muon System  

E-Print Network (OSTI)

The ability to provide fast muon triggering and efficient offline muon identification is an essential feature of the LHCb experiment. The muon detector is required to have a high efficiency over a large area and an appropriate time resolution to identify the bunch crossing for level–0 triggers. The LHCb muon detector consists of five stations equipped with 1368 Multi Wire Proportional Chambers and 12 Gas Electron Multiplier chambers. The technical design of the chambers is briefly presented and the Quality Control procedures during the various construction steps are described. The method developed for gas gain uniformity measurement is also described together with the results on efficiency of detectors fully equipped with the front–end electronics, obtained from tests with cosmic rays.

Lenzi, Michela

2005-01-01T23:59:59.000Z

266

A 4D Synchrotron X-Ray-Tomography Study of the Formation of Hydrocarbon- Migration Pathways in Heated Organic-Rich Shale  

Science Conference Proceedings (OSTI)

Recovery of oil from oil shales and the natural primary migration of hydrocarbons are closely related processes that have received renewed interest in recent years because of the ever tightening supply of conventional hydrocarbons and the growing production of hydrocarbons from low-permeability tight rocks. Quantitative models for conversion of kerogen into oil and gas and the timing of hydrocarbon generation have been well documented. However, lack of consensus about the kinetics of hydrocarbon formation in source rocks, expulsion timing, and how the resulting hydrocarbons escape from or are retained in the source rocks motivates further investigation. In particular, many mechanisms have been proposed for the transport of hydrocarbons from the rocks in which they are generated into adjacent rocks with higher permeabilities and smaller capillary entry pressures, and a better understanding of this complex process (primary migration) is needed. To characterize these processes, it is imperative to use the latest technological advances. In this study, it is shown how insights into hydrocarbon migration in source rocks can be obtained by using sequential high-resolution synchrotron X-ray tomography. Three-dimensional images of several immature "shale" samples were constructed at resolutions close to 5 um. This is sufficient to resolve the source-rock structure down to the grain level, but very-fine-grained silt particles, clay particles, and colloids cannot be resolved. Samples used in this investigation came from the R-8 unit in the upper part of the Green River shale, which is organic rich, varved, lacustrine marl formed in Eocene Lake Uinta, USA. One Green River shale sample was heated in situ up to 400 degrees C as X-ray-tomography images were recorded. The other samples were scanned before and after heating at 400 degrees C. During the heating phase, the organic matter was decomposed, and gas was released. Gas expulsion from the low-permeability shales was coupled with formation of microcracks. The main technical difficulty was numerical extraction of microcracks that have apertures in the 5- to 30-um range (with 5 um being the resolution limit) from a large 3D volume of X-ray attenuation data. The main goal of the work presented here is to develop a methodology to process these 3D data and image the cracks. This methodology is based on several levels of spatial filtering and automatic recognition of connected domains. Supportive petrographic and thermogravimetric data were an important complement to this study. An investigation of the strain field using 2D image correlation analyses was also performed. As one application of the 4D (space + time) microtomography and the developed workflow, we show that fluid generation was accompanied by crack formation. Under different conditions, in the subsurface, this might provide paths for primary migration.

Hamed Panahi; Paul Meakin; Francois Renard; Maya Kobchenko; Julien Scheibert; Adriano Mazzini; Bjorn Jamtveit; Anders Malthe-Sorenssen; Dag Kristian Dysthe

2013-04-01T23:59:59.000Z

267

The Effect of a Contrast Agent on Proton Beam Range in Radiotherapy Planning Using Computed Tomography for Patients With Locoregionally Advanced Lung Cancer  

SciTech Connect

Purpose: We evaluated the effect of a contrast agent (CA) on proton beam range in a treatment planning system (TPS) for patients with locoregionally advanced lung cancer. Methods and Materials: Two sets of computed tomography (CT) images (with and without CA) were obtained from 20 patients with lung cancer. Because the increase in Hounsfield unit ( Increment HU) value of the heart and great vessels due to the effect of CA is most prominent among thoracic structures, to evaluate the effect of CA on proton beam range in the TPS, we compared the calculated distal ranges in the plan with CA-enhanced CT with those with corrected CT, in which the HU values of the heart and great vessels in the CA-enhanced CT were replaced by average HU values obtained from the unenhanced CT. Results: The mean Increment HU value and the longest length of the heart and great vessels within the proton beam path in the field that passed through these structures were 189 {+-} 29 HU (range, 110-250 HU) and 7.1 {+-} 1.1 cm (range, 2.6-11.2 cm), respectively. The mean distal range error in the TPS because of the presence of CA was 1.0 {+-} 0.7 cm (range, 0.2-2.6 cm). Conclusion: If CA-enhanced CT images are used for radiotherapy planning using a proton beam for the treatment of lung cancer, our results suggest that the HU values of the heart and great vessels should be replaced by the average HU values of soft tissue to avoid discrepancies between planned and delivered doses.

Hwang, Ui-Jung; Shin, Dong Ho [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi (Korea, Republic of); Kim, Tae Hyun, E-mail: k2onco@naver.com [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi (Korea, Republic of); Moon, Sung Ho; Lim, Young Kyung; Jeong, Hojin; Rah, Jeong-Eun; Kim, Sang Soo; Kim, Joo-Young; Kim, Dae Yong; Park, Sung Yong; Cho, Kwan Ho [Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Gyeonggi (Korea, Republic of)

2011-11-15T23:59:59.000Z

268

Myocardial infarction determined by technetium-99m pyrophosphate single-photon tomography complicating elective coronary artery bypass grafting for angina pectoris  

SciTech Connect

The incidence of acute myocardial infarction (AMI) complicating coronary artery bypass grafting (CABG) has previously been based on concordance of electrocardiographic, enzymatic and scintigraphic criteria. Technetium-99m pyrophosphate (Tc-PPi) single-photon emission computed tomography now enables detection of AMI with high sensitivity and specificity. Using this technique, perioperative AMI was detected in 12 of 58 patients (21%) undergoing successful elective CABG for stable angina pectoris. Stepwise multivariate logistic regression analysis was performed to compare the predictive value of preoperative (New York Heart Association class, left ventricular ejection fraction and use of beta blockers) and intraoperative (number of grafts constructed, use of internal mammary anastomoses, use of sequential saphenous vein grafts, smallest grafted distal vessel lumen caliber and aortic cross-clamp time) variables. Preoperative New York Association class (p = 0.04) and smallest grafted distal vessel lumen caliber (p = 0.03) were significant multivariate predictors of perioperative AMI. Only 1 perioperative patient with AMI (and 1 pyrophosphate-negative patient) developed new Q waves. Serum creatine kinase-MB was higher in patients with AMI by repeated measures analysis of variance (p = 0.0003). Five AMIs occurred in myocardial segments revascularized using sequential saphenous vein grafts, and 7 in segments perfused by significantly stenosed epicardial vessels with distal lumen diameter and perfusion territory considered too small to warrant CABG. At 6-month follow-up, the mean left ventricular ejection fraction increased from 0.61 to 0.65 in Tc-PPI-negative patients (p = 0.01), but not in perioperative patients with AMI.

Burns, R.J.; Gladstone, P.J.; Tremblay, P.C.; Feindel, C.M.; Salter, D.R.; Lipton, I.H.; Ogilvie, R.R.; David, T.E.

1989-06-15T23:59:59.000Z

269

Association Between Pulmonary Uptake of Fluorodeoxyglucose Detected by Positron Emission Tomography Scanning After Radiation Therapy for Non-Small-Cell Lung Cancer and Radiation Pneumonitis  

Science Conference Proceedings (OSTI)

Purpose: To study the relationship between fluorodeoxyglucose (FDG) uptake in pulmonary tissue after radical radiation therapy (RT) and the presence and severity of radiation pneumonitis. Methods and Materials: In 88 consecutive patients, {sup 18}F-FDG-positron emission tomography was performed at a median of 70 days after completion of RT. Patients received 60 Gy in 30 fractions, and all but 15 had concurrent platinum-based chemotherapy. RT-induced pulmonary inflammatory changes occurring within the radiation treatment volume were scored, using a visual (0 to 3) radiotoxicity grading scale, by an observer blinded to the presence or absence of clinical radiation pneumonitis. Radiation pneumonitis was retrospectively graded using the Radiation Therapy Oncology Group (RTOG) scale by an observer blinded to the PET radiotoxicity score. Results: There was a significant association between the worst RTOG pneumonitis grade occurring at any time after RT and the positron emission tomograph (PET) radiotoxicity grade (one-sided p = 0.033). The worst RTOG pneumonitis grade occurring after the PET scan was also associated with the PET radiotoxicity grade (one-sided p = 0.035). For every one-level increase in the PET toxicity scale, the risk of a higher RTOG radiation pneumonitis score increased by approximately 40%. The PET radiotoxicity score showed no significant correlation with the duration of radiation pneumonitis. Conclusions: The intensity of FDG uptake in pulmonary tissue after RT determined using a simple visual scoring system showed significant correlation with the presence and severity of radiation pneumonitis. {sup 18}F-FDG-PET may be useful in the prediction, diagnosis and therapeutic monitoring of radiation pneumonitis.

Mac Manus, Michael P., E-mail: michael.macmanus@petermac.org [Department of Radiation Oncology, Peter MacCallum Cancer Institute, Melbourne (Australia); Ding Zhe [Department of Radiation Oncology, Affiliated Hospital of NingXia Medical University, YinChuan, NingXia (China); Hogg, Annette [Department of Diagnostic Imaging, Peter MacCallum Cancer Institute, Melbourne (Australia); Herschtal, Alan [Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Institute, Melbourne (Australia); Binns, David [Department of Diagnostic Imaging, Peter MacCallum Cancer Institute, Melbourne (Australia); Ball, David L. [Department of Radiation Oncology, Peter MacCallum Cancer Institute, Melbourne (Australia); Hicks, Rodney J. [Department of Diagnostic Imaging, Peter MacCallum Cancer Institute, Melbourne (Australia)

2011-08-01T23:59:59.000Z

270

Usefulness of Cone-Beam Computed Tomography During Ultraselective Transcatheter Arterial Chemoembolization for Small Hepatocellular Carcinomas that Cannot be Demonstrated on Angiography  

SciTech Connect

This study evaluated the usefulness of cone-beam computed tomography (CBCT) during ultraselective transcatheter arterial chemoembolization (TACE) for hepatocellular carcinomas (HCC) that could not be demonstrated on angiography. Twenty-eight patients with 33 angiographically occult tumors (mean diameter 1.3 {+-} 0.3 cm) were enrolled in the study. The ability of CBCT during arterial portography (CBCTAP), during hepatic arteriography (CBCTHA), and after iodized oil injection (LipCBCT) to detect HCC lesions was retrospectively analyzed. The technical success of TACE was divided into three grades: complete (the embolized area included the entire tumor with at least a 5-mm wide margin), adequate (the embolized area included the entire tumor but without a 5-mm wide margin in parts), and incomplete (the embolized area did not include the entire tumor) according to computed axial tomographic (CAT) images obtained 1 week after TACE. Local tumor progression was also evaluated. CBCTAP, CBCTHA, and LipCBCT detected HCC lesions in 93.9% (31 of 33), 96.7% (29 of 30), and 100% (29 of 29) of patients, respectively. A single branch was embolized in 28 tumors, and 2 branches were embolized in five tumors. Twenty-seven tumors (81.8%) were classed as complete, and 6 (18.2%) were classed as adequate. None of the tumors were classed as incomplete. Twenty-five tumors (75.8%) had not recurred during 12.0 {+-} 6.2 months. Eight tumors (24.2%), 5 (18.5%) of 27 complete success and 3 (50%) of 6 adequate success, recurred during 10.1 {+-} 6.2 months. CBCT during TACE is useful in detecting and treating small HCC lesions that cannot not be demonstrated on angiography.

Miyayama, Shiro, E-mail: s-miyayama@fukui.saiseikai.or.jp; Yamashiro, Masashi; Okuda, Miho; Yoshie, Yuichi; Sugimori, Natsuki; Igarashi, Saya; Nakashima, Yoshiko [Fukuiken Saiseikai Hospital, Department of Diagnostic Radiology (Japan); Matsui, Osamu [Kanazawa University Graduate School of Medical Science, Department of Radiology (Japan)

2009-03-15T23:59:59.000Z

271

Dosimetric Effect of Intrafraction Motion and Residual Setup Error for Hypofractionated Prostate Intensity-Modulated Radiotherapy With Online Cone Beam Computed Tomography Image Guidance  

SciTech Connect

Purpose: To quantify the dosimetric effect and margins required to account for prostate intrafractional translation and residual setup error in a cone beam computed tomography (CBCT)-guided hypofractionated radiotherapy protocol. Methods and Materials: Prostate position after online correction was measured during dose delivery using simultaneous kV fluoroscopy and posttreatment CBCT in 572 fractions to 30 patients. We reconstructed the dose distribution to the clinical tumor volume (CTV) using a convolution of the static dose with a probability density function (PDF) based on the kV fluoroscopy, and we calculated the minimum dose received by 99% of the CTV (D{sub 99}). We compared reconstructed doses when the convolution was performed per beam, per patient, and when the PDF was created using posttreatment CBCT. We determined the minimum axis-specific margins to limit CTV D{sub 99} reduction to 1%. Results: For 3-mm margins, D{sub 99} reduction was {<=}5% for 29/30 patients. Using post-CBCT rather than localizations at treatment delivery exaggerated dosimetric effects by {approx}47%, while there was no such bias between the dose convolved with a beam-specific and patient-specific PDF. After eight fractions, final cumulative D{sub 99} could be predicted with a root mean square error of <1%. For 90% of patients, the required margins were {<=}2, 4, and 3 mm, with 70%, 40%, and 33% of patients requiring no right-left (RL), anteroposterior (AP), and superoinferior margins, respectively. Conclusions: For protocols with CBCT guidance, RL, AP, and SI margins of 2, 4, and 3 mm are sufficient to account for translational errors; however, the large variation in patient-specific margins suggests that adaptive management may be beneficial.

Adamson, Justus [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Wayne State University, School of Medicine, Detroit, Michigan (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Wu Qiuwen, E-mail: Qiuwen.Wu@Duke.ed [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yan Di [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan (United States)

2011-06-01T23:59:59.000Z

272

Modeling pure methane hydrate dissociation using a numerical simulator from a novel combination of X-ray computed tomography and macroscopic data  

SciTech Connect

The numerical simulator TOUGH+HYDRATE (T+H) was used to predict the transient pure methane hydrate (no sediment) dissociation data. X-ray computed tomography (CT) was used to visualize the methane hydrate formation and dissociation processes. A methane hydrate sample was formed from granular ice in a cylindrical vessel, and slow depressurization combined with thermal stimulation was applied to dissociate the hydrate sample. CT images showed that the water produced from the hydrate dissociation accumulated at the bottom of the vessel and increased the hydrate dissociation rate there. CT images were obtained during hydrate dissociation to confirm the radial dissociation of the hydrate sample. This radial dissociation process has implications for dissociation of hydrates in pipelines, suggesting lower dissociation times than for longitudinal dissociation. These observations were also confirmed by the numerical simulator predictions, which were in good agreement with the measured thermal data during hydrate dissociation. System pressure and sample temperature measured at the sample center followed the CH{sub 4} hydrate L{sub w}+H+V equilibrium line during hydrate dissociation. The predicted cumulative methane gas production was within 5% of the measured data. Thus, this study validated our simulation approach and assumptions, which include stationary pure methane hydrate-skeleton, equilibrium hydrate-dissociation and heat- and mass-transfer in predicting hydrate dissociation in the absence of sediments. It should be noted that the application of T+H for the pure methane hydrate system (no sediment) is outside the general applicability limits of T+H.

Gupta, A.; Moridis, G.J.; Kneafsey, T.J.; Sloan, Jr., E.D.

2009-08-15T23:59:59.000Z

273

Megavoltage Cone Beam Computed Tomography Dose and the Necessity of Reoptimization for Imaging Dose-Integrated Intensity-Modulated Radiotherapy for Prostate Cancer  

Science Conference Proceedings (OSTI)

Purpose: Megavoltage cone beam computed tomography (MV-CBCT) dose can be integrated with the patient's prescription. Here, we investigated the effects of imaging dose and the necessity for additional optimization when using intensity-modulated radiotherapy (IMRT) to treat prostate cancer. Methods and Materials: An arc beam mimicking MV-CBCT was generated using XiO (version 4.50; Elekta, Stockholm, Sweden). The monitor units (MU) for dose calculation were determined by conforming the calculated dose to the dose measured using an ionization chamber. IMRT treatment plans of 22 patients with prostate cancer were retrospectively analyzed. Arc beams of 3, 5, 8, and 15 MU were added to the IMRT plans, and the dose covering 95% of the planning target volume (PTV) was normalized to the prescribed dose with (reoptimization) or without optimization (compensation). Results: PTV homogeneity and conformality changed negligibly with MV-CBCT integration. For critical organs, an imaging dose-dependent increase was observed for the mean rectal/bladder dose (D{sub mean}), and reoptimization effectively suppressed the D{sub mean} elevations. The bladder generalized equivalent uniform dose (gEUD) increased with imaging dose, and reoptimization suppressed the gEUD elevation when 5- to 15-MU CBCT were added, although rectal gEUD changed negligibly with any imaging dose. Whereas the dose elevation from the simple addition of the imaging dose uniformly increased rectal and bladder dose, the rectal D{sub mean} increase of compensation plans was due mainly to low-dose volumes. In contrast, bladder high-dose volumes were increased by integrating the CBCT dose, and reoptimization reduced them when 5- to 15-MU CBCT were added. Conclusion: Reoptimization is clearly beneficial for reducing dose to critical organs, elevated by addition of high-MU CBCT, especially for the bladder. For low-MU CBCT aimed at bony structure visualization, compensation is sufficient.

Akino, Yuichi [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka (Japan); Koizumi, Masahiko, E-mail: koizumi@radonc.med.osaka-u.ac.jp [Division of Medical Physics, Oncology Center, Osaka University Hospital, Suita, Osaka (Japan); Sumida, Iori; Takahashi, Yutaka; Ogata, Toshiyuki [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka (Japan); Division of Medical Physics, Oncology Center, Osaka University Hospital, Suita, Osaka (Japan); Ota, Seiichi [Division of Radiology, Department of Medical Technology, Osaka University Hospital, Suita, Osaka (Japan); Isohashi, Fumiaki; Konishi, Koji; Yoshioka, Yasuo [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Osaka (Japan)

2012-04-01T23:59:59.000Z

274

Muon Astronomy with LVD Detector  

E-Print Network (OSTI)

We analysed the arrival directions of single muons detected by the first LVD tower from November, 1994 till January, 1998. The moon shadowing effect has been observed. To search for point sources of high energy photons we have analysed muons crossing the rock thickness greater than 3, 5 and 7 km w.e., which corresponds to the mean muon energies 1.6, 3.9 and 8.4 TeV at the surface, respectively. Upper limits on steady muon fluxes for selected astrophysical sources for different muon energies are presented.

LVD Collaboration

1999-05-25T23:59:59.000Z

275

Geometric Tomography: A Limited-View Approach for Computed Tomography  

E-Print Network (OSTI)

- sitions is increasing to improve image quality which further increases patient radiation exposure as well of the internal organs of the body. As a result, CT is used routinely in the clinical arena to obtain three resulted in a substantial rise in population-radiation-dose [1], which may lead to an in- creased incidence

Corso, Jason J.

276

Image Guidance During Head-and-Neck Cancer Radiation Therapy: Analysis of Alignment Trends With In-Room Cone-Beam Computed Tomography Scans  

Science Conference Proceedings (OSTI)

Purpose: On-board cone-beam computed tomography (CBCT) is currently available for alignment of patients with head-and-neck cancer before radiotherapy. However, daily CBCT is time intensive and increases the overall radiation dose. We assessed the feasibility of using the average couch shifts from the first several CBCTs to estimate and correct for the presumed systematic setup error. Methods and Materials: 56 patients with head-and-neck cancer who received daily CBCT before intensity-modulated radiation therapy had recorded shift values in the medial-lateral, superior-inferior, and anterior-posterior dimensions. The average displacements in each direction were calculated for each patient based on the first five or 10 CBCT shifts and were presumed to represent the systematic setup error. The residual error after this correction was determined by subtracting the calculated shifts from the shifts obtained using daily CBCT. Results: The magnitude of the average daily residual three-dimensional (3D) error was 4.8 {+-} 1.4 mm, 3.9 {+-} 1.3 mm, and 3.7 {+-} 1.1 mm for uncorrected, five CBCT corrected, and 10 CBCT corrected protocols, respectively. With no image guidance, 40.8% of fractions would have been >5 mm off target. Using the first five CBCT shifts to correct subsequent fractions, this percentage decreased to 19.0% of all fractions delivered and decreased the percentage of patients with average daily 3D errors >5 mm from 35.7% to 14.3% vs. no image guidance. Using an average of the first 10 CBCT shifts did not significantly improve this outcome. Conclusions: Using the first five CBCT shift measurements as an estimation of the systematic setup error improves daily setup accuracy for a subset of patients with head-and-neck cancer receiving intensity-modulated radiation therapy and primarily benefited those with large 3D correction vectors (>5 mm). Daily CBCT is still necessary until methods are developed that more accurately determine which patients may benefit from alternative imaging strategies.

Zumsteg, Zachary; DeMarco, John; Lee, Steve P. [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Steinberg, Michael L. [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA (United States); Lin, Chun Shu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); McBride, William [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA (United States); Lin, Kevin; Wang, Pin-Chieh; Kupelian, Patrick [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Lee, Percy, E-mail: percylee@mednet.ucla.edu [Department of Radiation Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA (United States)

2012-06-01T23:59:59.000Z

277

Development and Implementation of 3-D, High Speed Capacitance Tomography for Imaging Large-Scale, Cold-Flow Circulating Fluidized Bed  

SciTech Connect

A detailed understanding of multiphase flow behavior inside a Circulating Fluidized Bed (CFB) requires a 3-D technique capable of visualizing the flow field in real-time. Electrical Capacitance Volume Tomography (ECVT) is a newly developed technique that can provide such measurements. The attractiveness of the technique is in its low profile sensors, fast imaging speed and scalability to different section sizes, low operating cost, and safety. Moreover, the flexibility of ECVT sensors enable them to be designed around virtually any geometry, rendering them suitable to be used for measurement of solid flows in exit regions of the CFB. Tech4Imaging LLC has worked under contract with the U.S. Department of Energyâ??s National Energy Technology Laboratory (DOE NETL) to develop an ECVT system for cold flow visualization and install it on a 12 inch ID circulating fluidized bed. The objective of this project was to help advance multi-phase flow science through implementation of an ECVT system on a cold flow model at DOE NETL. This project has responded to multi-phase community and industry needs of developing a tool that can be used to develop flow models, validate computational fluid dynamics simulations, provide detailed real-time feedback of process variables, and provide a comprehensive understating of multi-phase flow behavior. In this project, a complete ECVT system was successfully developed after considering different potential electronics and sensor designs. The system was tested at various flow conditions and with different materials, yielding real-time images of flow interaction in a gas-solid flow system. The system was installed on a 12 inch ID CFB of the US Department of Energy, Morgantown Labs. Technical and economic assessment of Scale-up and Commercialization of ECVT was also conducted. Experiments conducted with larger sensors in conditions similar to industrial settings are very promising. ECVT has also the potential to be developed for imaging multi-phase flow systems in high temperature and high pressure conditions, typical in many industrial applications.

Qussai Marashdeh

2012-09-30T23:59:59.000Z

278

On-Line Use of Three-Dimensional Marker Trajectory Estimation From Cone-Beam Computed Tomography Projections for Precise Setup in Radiotherapy for Targets With Respiratory Motion  

Science Conference Proceedings (OSTI)

Purpose: To develop and evaluate accurate and objective on-line patient setup based on a novel semiautomatic technique in which three-dimensional marker trajectories were estimated from two-dimensional cone-beam computed tomography (CBCT) projections. Methods and Materials: Seven treatment courses of stereotactic body radiotherapy for liver tumors were delivered in 21 fractions in total to 6 patients by a linear accelerator. Each patient had two to three gold markers implanted close to the tumors. Before treatment, a CBCT scan with approximately 675 two-dimensional projections was acquired during a full gantry rotation. The marker positions were segmented in each projection. From this, the three-dimensional marker trajectories were estimated using a probability based method. The required couch shifts for patient setup were calculated from the mean marker positions along the trajectories. A motion phantom moving with known tumor trajectories was used to examine the accuracy of the method. Trajectory-based setup was retrospectively used off-line for the first five treatment courses (15 fractions) and on-line for the last two treatment courses (6 fractions). Automatic marker segmentation was compared with manual segmentation. The trajectory-based setup was compared with setup based on conventional CBCT guidance on the markers (first 15 fractions). Results: Phantom measurements showed that trajectory-based estimation of the mean marker position was accurate within 0.3 mm. The on-line trajectory-based patient setup was performed within approximately 5 minutes. The automatic marker segmentation agreed with manual segmentation within 0.36 {+-} 0.50 pixels (mean {+-} SD; pixel size, 0.26 mm in isocenter). The accuracy of conventional volumetric CBCT guidance was compromised by motion smearing ({<=}21 mm) that induced an absolute three-dimensional setup error of 1.6 {+-} 0.9 mm (maximum, 3.2) relative to trajectory-based setup. Conclusions: The first on-line clinical use of trajectory estimation from CBCT projections for precise setup in stereotactic body radiotherapy was demonstrated. Uncertainty in the conventional CBCT-based setup procedure was eliminated with the new method.

Worm, Esben S., E-mail: esbeworm@rm.dk [Department of Oncology, Aarhus University Hospital, Aarhus (Denmark); Department of Medical Physics, Aarhus University Hospital, Aarhus (Denmark); Hoyer, Morten; Fledelius, Walther [Department of Oncology, Aarhus University Hospital, Aarhus (Denmark); Nielsen, Jens E.; Larsen, Lars P. [Department of Radiology, Aarhus University Hospital, Aarhus (Denmark); Poulsen, Per R. [Department of Oncology, Aarhus University Hospital, Aarhus (Denmark); Institute of Clinical Medicine, Aarhus University (Denmark)

2012-05-01T23:59:59.000Z

279

Acoustic tomography and conventional meteorological ...  

Science Conference Proceedings (OSTI)

Depending on the incoming solar radiation and the local advection regional ... wind field as well as in the vertical sensible heat fluxes were observed.

280

3D Atom Probe Tomography  

Science Conference Proceedings (OSTI)

... Specimen preparation often includes electropolishing for metals or FIB milling for any solid bulk specimen. Scientific Opportunities / Applications: ...

2012-10-04T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Tomography of the Solar Interior  

E-Print Network (OSTI)

Solar oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision Doppler images of the solar surface. The purpose of helioseismology is to retrieve information about the structure and the dynamics of the solar interior from the frequencies, phases, and amplitudes of solar waves. Methods of analysis are being developed to make three-dimensional images of subsurface motions and temperature inhomogeneities in order to study convective structures and regions of magnetic activity, like sunspots.

Gizon, L

2008-01-01T23:59:59.000Z

282

Tomography of the Solar Interior  

E-Print Network (OSTI)

Solar oscillations consist of a rich spectrum of internal acoustic waves and surface gravity waves, stochastically excited by turbulent convection. They have been monitored almost continuously over the last ten years with high-precision Doppler images of the solar surface. The purpose of helioseismology is to retrieve information about the structure and the dynamics of the solar interior from the frequencies, phases, and amplitudes of solar waves. Methods of analysis are being developed to make three-dimensional images of subsurface motions and temperature inhomogeneities in order to study convective structures and regions of magnetic activity, like sunspots.

L. Gizon

2008-03-27T23:59:59.000Z

283

Model Based HAADF STEM Tomography  

Science Conference Proceedings (OSTI)

P2-28: Characterization of Pores and Cracks in Underwater Welds by µCT and Digital Optical Microscopy · P3-01: 3D Visualisation of Crystallographic Pitting.

284

NK Muon Beam  

Science Conference Proceedings (OSTI)

The NK Muon Beam will be a modified version of the existing NT beam line. The decision to employ a modified version of the NT beam line was made based on considerations of cost and availability of the beam line. Preliminary studies considered use of other beam lines, e.g., the NW beam line, and even of moving the bubble chamber with its superconducting coils but were rejected for reasons such as cost, personnel limitations, and potential conflicts with other users.

Koizumi, G.

1988-09-28T23:59:59.000Z

285

muon_collider  

NLE Websites -- All DOE Office Websites (Extended Search)

muon_collider muon_collider muon_collider FridayMeetings MCTFmeetings MondayMeetings prstab texput.log #prstab.tex# last.kumac prstab.ps arxiv.tar.gz prstab.tar.gz referee_response_II.pdf prstab.pdf prstab.aux prstab.dvi prstab.end prstab.log prstab.tex prstab.tex~ accel-010307-f03.eps accel-010307-f28.eps old conclusions.tex higgsfact.tex introduction.tex mice.tex neufact.tex physics.tex prstab.tex r_and_d.tex authors_merged.tex buncher.tex temp.prt last.kumacold ringfig.eps MICE-fig.ps chgr_norm.ps chgr_merit.ps temp.csh temp.prt~ xupdn-a-model-view-iron5.eps site1-Layout1.eps rla2.eps phaserot.eps mole-hill.eps intoap.eps emit.eps cavity.eps allcount.eps MICE-88MHz-cooling.eps changes hh_ha_susy_rtsscan.eps letter_plots.eps scott33.eps scott32b.eps scott32a.eps MICE-200MHz-long.eps MICE-resolution.eps dipole_fields.eps

286

Muon Cooling R&D  

E-Print Network (OSTI)

International efforts are under way to design and test a muon ionization cooling channel. The present R&D program is described, and future plans outlined.

Steve Geer

2001-08-15T23:59:59.000Z

287

ATLAS Muon Spectrometer | Brookhaven and the LHC  

NLE Websites -- All DOE Office Websites (Extended Search)

ATLAS Muon Spectrometer small wheels Brookhaven National Laboratory led the development of the 32 muon detectors in the inner ring of the ATLAS detector's "small wheels." (A small...

288

Links to Muon Collider Related Web Pages  

NLE Websites -- All DOE Office Websites (Extended Search)

useful nu-factory related web pages: Nu-FactoryMuon Collider Studies at Fermilab Neutrino Factory Design Study MUCOOL Collaboration: Ionization Cooling R&D Brookhaven Muon...

289

Three-Dimensional Microstructure Visualization of Porosity and Fe-Rich Inclusions in SiC Particle-Reinforced Al Alloy Matrix Composites by X-Ray Synchrotron Tomography  

SciTech Connect

Microstructural aspects of composites such as reinforcement particle size, shape, and distribution play important roles in deformation behavior. In addition, Fe-rich inclusions and porosity also influence the behavior of these composites, particularly under fatigue loading. Three-dimensional (3-D) visualization of porosity and Fe-rich inclusions in three dimensions is critical to a thorough understanding of fatigue resistance of metal matrix composites (MMCs), because cracks often initiate at these defects. In this article, we have used X-ray synchrotron tomography to visualize and quantify the morphology and size distribution of pores and Fe-rich inclusions in a SiC particle-reinforced 2080 Al alloy composite. The 3-D data sets were also used to predict and understand the influence of defects on the deformation behavior by 3-D finite element modeling.

Silva, Flávio de Andrade; Williams, Jason J.; Müller, Bernd R.; Hentschel, Manfred P.; Portella, Pedro D.; Chawla, Nikhilesh

2011-11-15T23:59:59.000Z

290

Research and Development of Future Muon Collider  

SciTech Connect

Muon collider is a considerable candidate of the next generation high-energy lepton collider machine. A novel accelerator technology must be developed to overcome several intrinsic issues of muon acceleration. Recent research and development of critical beam elements for a muon accelerator, especially muon beam phase space ionization cooling channel, are reviewed in this paper.

Yonehara, K.; /Fermilab

2012-05-01T23:59:59.000Z

291

Stochastic cooling in muon colliders  

SciTech Connect

Analysis of muon production techniques for high energy colliders indicates the need for rapid and effective beam cooling in order that one achieve luminosities > 10{sup 30} cm{sup {minus}2}s{sup {minus}1} as required for high energy physics experiments. This paper considers stochastic cooling to increase the phase space density of the muons in the collider. Even at muon energies greater than 100 GeV, the number of muons per bunch must be limited to {approximately}10{sup 3} for the cooling rate to be less than the muon lifetime. With such a small number of muons per bunch, the final beam emittance implied by the luminosity requirement is well below the thermodynamic limit for beam electronics at practical temperatures. Rapid bunch stacking after the cooling process can raise the number of muons per bunch to a level consistent with both the luminosity goals and with practical temperatures for the stochastic cooling electronics. A major advantage of our stochastic cooling/stacking scheme over scenarios that employ only ionization cooling is that the power on the production target can be reduced below 1 MW.

Barletta, W.A.; Sessler, A.M.

1993-09-01T23:59:59.000Z

292

LANL | TT | R&D 100 Awards | 2007 Summaries  

Muon tomography scanners will greatly increase border security against nuclear ... the fuel efficiency of commercial ... and hydrological cycle ;

293

Muon Collaboration Friday Meetings  

NLE Websites -- All DOE Office Websites (Extended Search)

Collaboration Friday Meetings Collaboration Friday Meetings Muon Collaboration Friday Meetings are held at Fermilab, in the Snakepit (WH 2E), at 1:30 pm CDT/CST on most Fridays. An audio bridge is available, details are in the meeting notice. To receive the weekly meeting notice, either join the NuMu-Collaboration-l mailing list or send email to Terry Hart (look me up in the FNAL Phonebook). 13-NOV-2009 Agenda Zisman.pdf 30-OCT-2009 Agenda Bross.ppt Ankenbrandt.ppt 22-OCT-2009 Agenda Fernow_1.pdf Fernow_2.pdf Snopok.pdf Palmer.pdf 16-OCT-2009 Agenda News Alexahin.ppt Alexakhin.pdf 9-OCT-2009 Agenda Yonehara.ppt 8-OCT-2009 Agenda Kirk.pdf 1-OCT-2009 Agenda Lamm.pdf 25-SEP-2009 Agenda Fernow.pdf 24-SEP-2009 Agenda 18-SEP-2009 Derun.pptx 17-SEP-2009 popovic.ppt 10-SEP-2009 Action_items.doc Bross.ppt Agenda 4-SEP-2009 Kaplan.pdf

294

Muon - proton inelastic scattering  

DOE Green Energy (OSTI)

This experiment will examine muon-proton inelastic scattering for virtual-photon energies of 10 to 110 GeV and for |q{sup 2}| values of 0.2 to 20.0 (GeV/c){sup 2}. The virtual-photon total cross sections {sigma}{sub t} + {epsilon}{sigma}{sub s}, or the equivalent expression in W{sub 1} and W{sub 2}, will be measured over this range of virtual-photon energies and q{sup 2} values. Some separation of {sigma}{sub T} and {sigma}{sub S}, or equivalently W{sub 1} and W{sub 2}, will be made. The multiplicity, momentum spectra and angular spectra of the charged hadrons produced in this reaction will be measured. Some channels such as {mu} + P {yields} {mu} + P + P{sup 0} will be isolated and completely analyzed. The experiment uses a hydrogen target, wire spark chambers and an analyzing magnet of conventional design.

Dieterle, B.; Lakin, W.; Martin, F.; Perl, M.; Petraske, E.; Tenebaum, J.; Toner, W.; Zipf, T.; /SLAC

1970-05-01T23:59:59.000Z

295

Law of Conservation of Muons  

DOE R&D Accomplishments (OSTI)

A multiplicative selection rule for mu meson-electron transitions is proposed. A "muon parity" = -1 is considered for the muon and its neutrino, while the "muon parity" for all other particles is +1. The selection rule then states that (-1) exp(no. of initial (-1) parity particles) = (-1) exp(no. of final (-1) parity particles). Several reactions that are forbidden by an additive law but allowed by the multiplicative law are suggested; these reactions include mu{sup +} .> e{sup +} + nu{sub mu} + {ovr nu}{sub e}, e{sup -} + e{sup -} .> mu{sup -} + mu{sup -}, and muonium .> antimuonium (mu{sup +} + e{sup -} .> mu{sup -} + e{sup +}). An intermediate-boson hypothesis is suggested. (T.F.H.)

Feinberg, G.; Weinberg, S.

1961-02-00T23:59:59.000Z

296

Prompt muon contribution to the flux underwater  

E-Print Network (OSTI)

We present high energy spectra and zenith-angle distributions of the atmospheric muons computed for the depths of the locations of the underwater neutrino telescopes. We compare the calculations with the data obtained in the Baikal and the AMANDA muon experiments. The prompt muon contribution to the muon flux underwater due to recent perturbative QCD-based models of the charm production is expected to be observable at depths of the large underwater neutrino telescopes. This appears to be probable even at rather shallow depths (1-2 km), provided that the energy threshold for muon detection is raised above $\\sim 100$ TeV.

T. S. Sinegovskaya; S. I. Sinegovsky

2000-07-21T23:59:59.000Z

297

NEUTRINO FACTORY BASED ON MUON-STORAGE-RINGS TO MUON COLLIDERS: PHYSICS AND FACILITIES.  

Science Conference Proceedings (OSTI)

Intense muon sources for the purpose of providing intense high energy neutrino beams ({nu} factory) represents very interesting possibilities. If successful, such efforts would significantly advance the state of muon technology and provides intermediate steps in technologies required for a future high energy muon collider complex. High intensity muon: production, capture, cooling, acceleration and multi-turn muon storage rings are some of the key technology issues that needs more studies and developments, and will briefly be discussed here. A muon collider requires basically the same number of muons as for the muon storage ring neutrino factory, but would require more cooling, and simultaneous capture of both {+-} {mu}. We present some physics possibilities, muon storage ring based neutrino facility concept, site specific examples including collaboration feasibility studies, and upgrades to a full collider.

PARSA,Z.

2001-06-18T23:59:59.000Z

298

Muon capture on Chlorine-35  

E-Print Network (OSTI)

We report measurements of $\\gamma$--ray spectra from muon capture on $^{35}$Cl. For the allowed Gamow--Teller transitions to the $^{35}$S$(2939, 3/2^+)$ state and the $^{35}$S$(3421, 5/2^+)$ state we obtained their capture rates, hyperfine dependences and $\\gamma$--$\

S. Arole; D. S. Armstrong; T. P. Gorringe; M. D. Hasinoff; M. A. Kovash; V. Kuzmin; B. A. Moftah; R. Sedlar; T. J. Stocki; T. Tetereva

2002-04-30T23:59:59.000Z

299

Pelvic Lymph Node Status Assessed by 18F-Fluorodeoxyglucose Positron Emission Tomography Predicts Low-Risk Group for Distant Recurrence in Locally Advanced Cervical Cancer: A Prospective Study  

SciTech Connect

Purpose: To develop a prediction model to identify a low-risk group for distant recurrence in patients with locally advanced cervical cancer treated by concurrent chemoradiation. Methods and Materials: Prospectively, 62 patients with locally advanced cervical cancer were recruited as a training cohort. Clinical variables and parameters obtained from positron emission tomography (PET) and magnetic resonance imaging were analyzed by logistic regression. For the test set, 54 patients were recruited independently. To identify the low-risk group, negative likelihood ratio (LR) less than 0.2 was set to be a cutoff. Results: Among the training cohort, multivariate logistic analysis revealed that advanced International Federation of Gynecology and Obstetrics (FIGO) stage and a high serum squamous cancer cell (SCC) antigen level were significant risk factors (p = 0.015 and 0.025, respectively). Using the two parameters, criteria to determine a low-risk subset for distant recurrence were postulated: (1) FIGO Stage IIB or less and (2) pretreatment SCC < 2.4 (Model A). Positive pelvic node on PET completely predicted all cases with distant recurrence and thus was considered as another prediction model (Model B). In the test cohort, although Model A did not showed diagnostic performance, Model B completely predicted all cases with distant recurrence and showed a sensitivity of 100% with negative LR of 0. Across the training and test cohort (n = 116), the false negative rate was 0 (95% confidence interval 0%-7.6%). Conclusions: Positive pelvic node on PET is a useful marker in prediction of distant recurrence in patients with locally advanced cervical cancer who are treated with concurrent chemoradiation.

Kang, Sokbom, E-mail: sokbom@ncc.re.k [Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Park, Jung-Yeol; Lim, Myung-Chul; Song, Yong-Joong; Park, Se-Hyun [Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Kim, Seok-Ki [Center for Diagnostic Oncology, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of); Chung, Dae-Chul; Seo, Sang-Soo; Kim, Joo-Young; Park, Sang-Yoon [Center for Uterine Cancer, Research Institute and Hospital, National Cancer Center, Goyang (Korea, Republic of)

2011-03-01T23:59:59.000Z

300

Muon ID at the ILC  

SciTech Connect

This paper describes a new way to reconstruct and identify muons with high efficiency and high pion rejection. Since muons at the ILC are often produced with or in jets, for many of the physics channels of interest [1], an efficient algorithm to deal with the identification and separation of particles within jets is important. The algorithm at the core of the method accounts for the effects of the magnetic field and for the loss of energy by charged particles due to ionization in the detector. We have chosen to develop the analysis within the setup of one of the Linear Collider Concept Detectors adopted by the US. Within b-pair production jets, particles cover a wide range in momenta; however {approx}80% of the particles have a momentum below 30 GeV[2]. Our study, focused on bbar-b jets, is preceded by a careful analysis of single energy particles between 2 and 50 GeV. As medium energy particles are a substantial component of the jets, many of the particles lose part of their energy in the calorimeters and the solenoid coil before reaching the muon detector where they may have energy below 2 GeV. To deal with this problem we have implemented a Runge-Kutta correction of the calculated trajectory to better handle these lower energy particles. The multiple scattering and other stochastic processes, more important at lower energy, is addressed by a Kalman-filter integrated into the reconstruction algorithm. The algorithm provides a unique and powerful separation of muons from pions. The 5 Tesla magnetic field from a solenoid surrounds the hadron calorimeter and allows the reconstruction and precision.

Milstene, C.; Fisk, G.; Para, A.; /Fermilab

2006-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

The US Muon Accelerator Program (MAP)  

SciTech Connect

The US Department of Energy Office of High Energy Physics has recently approved a Muon Accelerator Program (MAP). The primary goal of this effort is to deliver a Design Feasibility Study for a Muon Collider after a 7 year R&D program. This paper presents a brief physics motivation for, and the description of, a Muon Collider facility and then gives an overview of the program. I will then describe in some detail the primary components of the effort.

Bross, Alan D.; /Fermilab

2010-12-01T23:59:59.000Z

302

Commissioning of the ATLAS Muon Trigger Selection  

E-Print Network (OSTI)

The performance of the three-level ATLAS muon trigger as evaluated by using LHC data is presented. Events have been selected by using only the hardware-based Level-1 trigger in order to commission and to subsequently enable the (software-based) selections of the High Level Trigger. Studies aiming at selecting prompt muons from J/{\\psi} and at reducing non prompt muon contamination have been performed. A brief overview on how the muon triggers evolve with increasing luminosity is given.

Musto, Elisa

2010-01-01T23:59:59.000Z

303

Commissioning of the ATLAS Muon Trigger Selection  

E-Print Network (OSTI)

The performance of the three-level ATLAS muon trigger as evaluated by using LHC data is presented. Events have been selected by using only the hardware-based Level-1 trigger in order to commission and to subsequently enable the (software-based) selections of the High Level Trigger. Studies aiming at selecting prompt muons from J/{\\psi} and at reducing non prompt muon contamination have been performed. A brief overview on how the muon triggers evolve with increasing luminosity is given.

Elisa Musto

2010-09-30T23:59:59.000Z

304

Muons in minimum bias events from the first CMS data  

Science Conference Proceedings (OSTI)

Muon signatures are extremely important in the challenging environment of collisions at the LHC. Understanding the observed muon yield from Standard Model processes is the first task for all analyses involving muons. Basic muon kinematical observables are presented for the first CMS data at s ?=?7? TeV and compared with Monte Carlo expectations. The muon sample composition is studied by using the MC truth in terms of muons from heavy flavours

Lucia Barbone; The CMS Collaboration

2010-01-01T23:59:59.000Z

305

Cold fusion catalyzed by muons and electrons  

SciTech Connect

Two alternative methods have been suggested to produce fusion power at low temperature. The first, muon catalyzed fusion or MCF, uses muons to spontaneously catalyze fusion through the muon mesomolecule formation. Unfortunately, this method fails to generate enough fusion energy to supply the muons, by a factor of about ten. The physics of MCF is discussed, and a possible approach to increasing the number of MCF fusions generated by each muon is mentioned. The second method, which has become known as Cold Fusion,'' involves catalysis by electrons in electrolytic cells. The physics of this process, if it exists, is more mysterious than MCF. However, it now appears to be an artifact, the claims for its reality resting largely on experimental errors occurring in rather delicate experiments. However, a very low level of such fusion claimed by Jones may be real. Experiments in cold fusion will also be discussed.

Kulsrud, R.M.

1990-10-01T23:59:59.000Z

306

Milky Way Tomography IV: Dissecting Dust  

SciTech Connect

We use SDSS photometry of 73 million stars to simultaneously obtain best-fit main-sequence stellar energy distribution (SED) and amount of dust extinction along the line of sight towards each star. Using a subsample of 23 million stars with 2MASS photometry, whose addition enables more robust results, we show that SDSS photometry alone is sufficient to break degeneracies between intrinsic stellar color and dust amount when the shape of extinction curve is fixed. When using both SDSS and 2MASS photometry, the ratio of the total to selective absorption, R{sub V}, can be determined with an uncertainty of about 0.1 for most stars in high-extinction regions. These fits enable detailed studies of the dust properties and its spatial distribution, and of the stellar spatial distribution at low Galactic latitudes (|b| < 30{sup o}). Our results are in good agreement with the extinction normalization given by the Schlegel et al. (1998, SFD) dust maps at high northern Galactic latitudes, but indicate that the SFD extinction map appears to be consistently overestimated by about 20% in the southern sky, in agreement with recent study by Schlafly et al. (2010). The constraints on the shape of the dust extinction curve across the SDSS and 2MASS bandpasses disfavor the reddening law of O'Donnell (1994), but support the models by Fitzpatrick (1999) and Cardelli et al. (1989). For the latter, we find a ratio of the total to selective absorption to be R{sub V} = 3.0 {+-} 0.1(random) {+-} 0.1 (systematic) over most of the high-latitude sky. At low Galactic latitudes (|b| < 5{sup o}), we demonstrate that the SFD map cannot be reliably used to correct for extinction because most stars are embedded in dust, rather than behind it, as is the case at high Galactic latitudes. We analyze three-dimensional maps of the best-fit R{sub V} and find that R{sub V} = 3.1 cannot be ruled out in any of the ten SEGUE stripes at a precision level of {approx} 0.1 - 0.2. Our best estimate for the intrinsic scatter of R{sub V} in the regions probed by SEGUE stripes is {approx} 0.2. We introduce a method for efficient selection of candidate red giant stars in the disk, dubbed 'dusty parallax relation', which utilizes a correlation between distance and the extinction along the line of sight. We make these best-fit parameters, as well as all the input SDSS and 2MASS data, publicly available in a user-friendly format. These data can be used for studies of stellar number density distribution, the distribution of dust properties, for selecting sources whose SED differs from SEDs for high-latitude main sequence stars, and for estimating distances to dust clouds and, in turn, to molecular gas clouds.

Berry, Michael; /Washington U., Seattle, Astron. Dept. /Rutgers U., Piscataway; Ivezic, Zeljko; /Washington U., Seattle, Astron. Dept.; Sesar, Branimir; /Caltech; Juric, Mario; /Harvard U., Phys. Dept.; Schlafly, Edward F.; /Harvard-Smithsonian Ctr. Astrophys.; Bellovary, Jillian; /Michigan U.; Finkbeiner, Douglas; /Harvard-Smithsonian Ctr. Astrophys.; Vrbanec, Dijana; /Zagreb U.; Beers, Timothy C.; /Natl. Solar Observ., Tucson; Brooks, Keira J.; /Washington U., Seattle, Astron. Dept.; Schneider, Donald P.; /Penn State U. /Washington U., Seattle, Astron. Dept.

2011-11-01T23:59:59.000Z

307

Computed Tomography (CT) Scanning For Petrophysical Applications  

NLE Websites -- All DOE Office Websites (Extended Search)

R&D Fac R&D Fac ts Carbon Sequestration ContaCtS David Wildman Division Director Geosciences Division National Energy Technology Laboratory 626 Cochrans Mill Road P.O. Box 10940 Pittsburgh, PA 15236 412-386-4913 david.wildman@netl.doe.gov T. Robert McLendon Geosciences Division National Energy Technology Laboratory 3610 Collins Ferry Road P.O. Box 880 Morgantown, WV 26507 304-285-2008 t.mclen@netl.doe.gov Duane H. Smith Geosciences Division

308

Ultrasonic Computerized Tomography of Pipelines for Continuous ...  

Science Conference Proceedings (OSTI)

Commercial handheld thickness gauging devices require direct access to pipelines and find limited applications due to the presence of physical obstacles or the ...

309

Adaptive Optics-Based Optical Coherence Tomography  

City of Livermore. Community. Our Community. Discovery Center. Site Tours. LLNL Community News. ... LLC, for the Department of Energy's National Nucle ...

310

Rocket plume tomography of combustion species .  

E-Print Network (OSTI)

??Interest in accurate detection and targeting of aggressor missiles has received considerable interest with the national priority of developing a missile defense system. Understanding the… (more)

Kutrieb, Joshua M.

2001-01-01T23:59:59.000Z

311

Classification of breast computed tomography data  

Science Conference Proceedings (OSTI)

Differences in breast tissue composition are important determinants in assessing risk, identifying disease in images and following changes over time. This paper presents an algorithm for tissue classification that separates breast tissue into its three primary constituents of skin, fat and glandular tissue. We have designed and built a dedicated breast CT scanner. Fifty-five normal volunteers and patients with mammographically identified breast lesions were scanned. Breast CT voxel data were filtered using a 5 pt median filter and the image histogram was computed. A two compartment Gaussian fit of histogram data was used to provide an initial estimate of tissue compartments. After histogram analysis, data were input to region-growing algorithms and classified as to belonging to skin, fat or gland based on their value and architectural features. Once tissues were classified, a more detailed analysis of glandular tissue patterns and a more quantitative analysis of breast composition was made. Algorithm performance assessment demonstrated very good or excellent agreement between algorithm and radiologist observers in 97.7% of the segmented data. We observed that even in dense breasts the fraction of glandular tissue seldom exceeded 50%. For most individuals the composition is better characterized as being a 70% (fat)-30% (gland) composition than a 50% (fat)-50% (gland) composition.

Nelson, Thomas R.; Cervino, Laura I.; Boone, John M.; Lindfors, Karen K. [Department of Radiology, University of California, San Diego, La Jolla, California 92037-0610 (United States); University of California Davis Medical Center, 4860 Y Street, Ambulatory Care Center Suite 3100, Sacramento, California 95817 (United States)

2008-03-15T23:59:59.000Z

312

System and method for ultrasonic tomography  

DOE Patents (OSTI)

A system and method for doing both transmission mode and reflection mode three-dimensional ultrasonic imagining. The multimode imaging capability may be used to provide enhanced detectability of cancer tumors within human breast, however, similar imaging systems are applicable to a number of other medical problems as well as a variety of non-medical problems in non-destructive evaluation (NDE).

Haddad, Waleed Sami (Dublin, CA)

2002-01-01T23:59:59.000Z

313

Quantum process tomography with coherent states  

E-Print Network (OSTI)

We develop an enhanced technique for characterizing quantum optical processes based on probing unknown quantum processes only with coherent states. Our method substantially improves the original proposal [M. Lobino et al., Science 322, 563 (2008)], which uses a filtered Glauber-Sudarshan decomposition to determine the effect of the process on an arbitrary state. We introduce a new relation between the action of a general quantum process on coherent state inputs and its action on an arbitrary quantum state. This relation eliminates the need to invoke the Glauber-Sudarshan representation for states; hence it dramatically simplifies the task of process identification and removes a potential source of error. The new relation also enables straightforward extensions of the method to multi-mode and non-trace-preserving processes. We illustrate our formalism with several examples, in which we derive analytic representations of several fundamental quantum optical processes in the Fock basis. In particular, we introduce photon-number cutoff as a reasonable physical resource limitation and address resource vs accuracy trade-off in practical applications. We show that the accuracy of process estimation scales inversely with the square root of photon-number cutoff.

Saleh Rahimi-Keshari; Artur Scherer; Ady Mann; Ali T. Rezakhani; A. I. Lvovsky; Barry C. Sanders

2010-09-17T23:59:59.000Z

314

NIST: Neutron Tomography of Hydrogen Storage Bed  

Science Conference Proceedings (OSTI)

... Future hydrogen fuel cell vehicles will require hydrogen storage vessels that ... will require understanding the coupled heat and mass transport system ...

2013-07-23T23:59:59.000Z

315

Applying Compactness Constraints to Differential Traveltime Tomography  

E-Print Network (OSTI)

Tomographic imaging problems are typically ill-posed and often require the use of regularization techniques

Ajo-Franklin, Jonathan B.

2007-01-01T23:59:59.000Z

316

Quantitative Phase Imaging by Digital Holographic Tomography  

quantitative information about the 3-D position of structures within a sample. ... consistent results ... Measurement Science and Systems Engineering

317

Positron emission tomography and optical tissue imaging  

Science Conference Proceedings (OSTI)

A mobile compact imaging system that combines both PET imaging and optical imaging into a single system which can be located in the operating room (OR) and provides faster feedback to determine if a tumor has been fully resected and if there are adequate surgical margins. While final confirmation is obtained from the pathology lab, such a device can reduce the total time necessary for the procedure and the number of iterations required to achieve satisfactory resection of a tumor with good margins.

Falen, Steven W. (Carmichael, CA); Hoefer, Richard A. (Newport News, VA); Majewski, Stanislaw (Yorktown, VA); McKisson, John (Hampton, VA); Kross, Brian (Yorktown, VA); Proffitt, James (Newport News, VA); Stolin, Alexander (Newport News, VA); Weisenberger, Andrew G. (Yorktown, VA)

2012-05-22T23:59:59.000Z

318

Echo Tomography of Black Hole Accretion Flows  

E-Print Network (OSTI)

We discuss technologies for micro-arcsec echo mapping of black hole accretion flows in Active Galactic Nuclei (AGN). Echo mapping employs time delays, Doppler shifts, and photoionisation physics to map the geometry, kinematics, and physical conditions in the reprocessing region close to a compact time-variable source of ionizing radiation. Time delay maps are derived from detailed analysis of variations in lightcurves at different wavelengths. Echo mapping is a maturing technology at a stage of development similar to that of radio interferometry just before the VLA. The first important results are in, confirming the basic assumptions of the method, measuring the sizes of AGN emission line regions, delivering dozens of black hole masses, and showing the promise of the technique. Resolution limits with existing AGN monitoring datasets are typically ~5-10 light days. This should improve down to 1-2 light days in the next-generation echo mapping experiments, using facilities like Kronos and Robonet that are designed for and dedicated to sustained spectroscopic monitoring. A light day is 0.4 micro-arcsec at redshift 0.1, thus echo mapping probes regions 10^3 times smaller than VLBI, and 10^5 times smaller than HST.

Keith Horne

2003-01-14T23:59:59.000Z

319

Development of novel emission tomography system.  

E-Print Network (OSTI)

??In recent years, small animals, such as mice and rats, have been widely used as subjects of study in biomedical research while molecular biology and… (more)

Fu, Geng

2011-01-01T23:59:59.000Z

320

Open charm tomography of cold nuclear matter  

E-Print Network (OSTI)

We study the relative contribution of partonic sub-processes to D meson production and D meson-triggered inclusive di-hadrons to lowest order in perturbative QCD. While gluon fusion dominates the creation of large angle DD-bar pairs, charm on light parton scattering determines the yield of single inclusive D mesons. The distinctly different non-perturbative fragmentation of c quarks into D mesons versus the fragmentation of quarks and gluons into light hadrons results in a strong transverse momentum dependence of anticharm content of the away-side charm-triggered jet. In p+A reactions, we calculate and resum the coherent nuclear-enhanced power corrections from the final state partonic scattering in the medium. We find that single and double inclusive open charm production can be suppressed as much as the yield of neutral pions from dynamical high-twist shadowing. Effects of energy loss in p+A collisions are also investigated phenomenologically and may lead to significantly weaker transverse momentum dependence of the nuclear attenuation.

I. Vitev; T. Goldman; M. B. Johnson; J. W. Qiu

2006-05-17T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

The Milky Way Tomography with SDSS  

E-Print Network (OSTI)

Using the photometric parallax method, we estimate the distances to ~48 million stars detected by the Sloan Digital Sky Survey (SDSS), and map their three-dimensional number density distribution in the Galaxy. The data show strong evidence for a Galaxy consisting of an oblate halo, disk components, and a number of localized overdensities. The number density distribution of stars in the Solar neighborhood (D < 1.5kpc) favors a model having a ``thin'' and a ``thick'' exponential disk, with scale heights and lengths of H_1 ~ 280pc and L_1 ~ 2400pc, and H_2 ~ 1200pc and L_2 ~ 3500pc, respectively, and local thick-to-thin disk normalization \\rho_{thick}(R_\\odot)/\\rho_{thin}(R_\\odot) = 4%. The halo power law index is very poorly constrained, but we find an oblate halo with c/a ~ 0.5 to be strongly preferred. In addition to known features, a remarkable density enhancement covering over a thousand square degrees of sky is detected towards the constellation of Virgo, at distances of ~5-15 kpc, and is responsible fo...

Juric, M; Brooks, A; Lupton, R H; Schlegel, D J; Finkbeiner, D; Padmanabhan, N; Bond, N; Rockosi, C M; Knapp, G R; Gunn, J E; Sumi, T; Schneider, D; Barentine, J C; Brewington, H J; Brinkmann, J; Fukugita, M; Harvanek, M; Kleinman, S J; Krzesínski, J; Long, D; Neilsen, E H; Nitta, A; Snedden, S A; York, D G; Juric, Mario; Ivezic, Zeljko; Brooks, Alyson; Lupton, Robert H.; Schlegel, David; Finkbeiner, Douglas; Padmanabhan, Nikhil; Bond, Nicholas; Rockosi, Constance M.; Knapp, Gillian R.; Gunn, James E.; Sumi, Takahiro; Schneider, Donald; Brewington, Howard J.; Fukugita, Masataka; Harvanek, Michael; Krzesinski, Jurek; Long, Dan; Neilsen, Eric H.; Nitta, Atsuko; Snedden, Stephanie A.; York, Donald G.

2005-01-01T23:59:59.000Z

322

The milky way tomography with sdss  

Science Conference Proceedings (OSTI)

Using the photometric parallax method, we estimate the distances to {approx}48 million stars detected by the Sloan Digital Sky Survey (SDSS), and map their three-dimensional number density distribution in the Galaxy. The currently available data sample the distance range from 100 pc to 15 kpc and cover 6,500 deg{sup 2} of sky, mostly at high galactic latitudes (|b| > 25). These stellar number density maps allow an investigation of the Galactic structure without any a priori assumptions about its components. The data show strong evidence for a Galaxy consisting of an oblate halo, disk components, and a number of localized overdensities. The number density distribution of stars in the Solar neighborhood (D < 1.5kpc) favors a model having a ''thin'' and a ''thick'' exponential disk, with scale heights and lengths of H{sub 1} {approx} 280 pc and L{sub 1} {approx} 2400pc, and H{sub 2} {approx} 1200pc and L{sub 2} {approx} 3500pc, respectively, and local thick-to-thin disk normalization {rho}{sub thick} (R{sub {circle_dot}})/{rho}{sub thin}(R{sub {circle_dot}}) = 4%. Fits applied to the entire dataset are significantly more uncertain due to the presence of clumps and overdensities. The halo power law index is very poorly constrained, but we find an oblate halo with c/a {approx} 0.5 to be strongly preferred. While roughly consistent with this simple model, the measured density distribution shows a number of statistically significant deviations from the model predictions. In addition to known features, such as the Monoceros stream, a remarkable density enhancement covering over a thousand square degrees of sky is detected towards the constellation of Virgo, at distances of {approx} 5-15 kpc. Compared to counts in a region symmetric with respect to the l = 0 line and with the same Galactic latitude, it is responsible for a factor of 2 number density excess, and may be a nearby tidal stream or a low-surface brightness dwarf galaxy merging with the Milky Way. The u - g color distribution of these stars implies metallicities lower than those of the thick disk, and consistent with the halo metallicity distribution.

Juric, Mario; Ivezic, Zeljko; Brooks, Alyson; Lupton, Robert H.; Schlegel, David; Finkbeiner, Douglas; Padmanabhan, Nikhil; Bond, Nicholas; Rockosi, Constance M.; Knapp, Gillian R.; Gunn, James E.; Sumi, Takahiro; Schneider, Donald; Barentine, J.C.; Brewington, Howard J.; Brinkmann, J.; Fukugita, Masataka; Harvanek, Michael; Kleinman, S.J.; Krzesinski, Jurek; Long, Dan; /Princeton U. Observ. /Washington U., Seattle, Astron. Dept. /Princeton U. /Penn State U., Astron. Astrophys. /Apache Point Observ. /Tokyo U., ICRR /Mt. Suhora Observ., Cracow /Fermilab /Chicago U., Astron. Astrophys. Ctr.

2005-10-01T23:59:59.000Z

323

The Cosmic Ray Muon Flux at WIPP  

E-Print Network (OSTI)

In this work a measurement of the muon intensity at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM, USA is presented. WIPP is a salt mine with a depth of 655 m. The vertical muon flux was measured with a two panels scintillator coincidence setup to Phi_{vert}=3.10(+0.05/-0.07)*10^(-7)s^(-1)cm^(-2)sr^(-1).

E. -I. Esch; T. J. Bowles; A. Hime; A. Pichlmaier; R. Reifarth; H. Wollnik

2004-08-25T23:59:59.000Z

324

The Cosmic Ray Muon Flux at WIPP  

E-Print Network (OSTI)

In this work a measurement of the muon intensity at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM, USA is presented. WIPP is a salt mine with a depth of 655 m. The vertical muon flux was measured with a two panels scintillator coincidence setup to ?vert = (3.10 +0.05 ?0.07) 10?7 s ?1 cm ?2 sr ?1.

E. -i. Esch A; T. J. Bowles A; A. Hime A; A. Pichlmaier A; R. Reifarth A; H. Wollnik B

2004-01-01T23:59:59.000Z

325

The Cosmic Ray Muon Flux at WIPP  

E-Print Network (OSTI)

In this work a measurement of the muon intensity at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, NM, USA is presented. WIPP is a salt mine with a depth of 655 m. The vertical muon flux was measured with a two panels scintillator coincidence setup to Phi_{vert}=3.10(+0.05/-0.07)*10^(-7)s^(-1)cm^(-2)sr^(-1).

Esch, E I; Hime, A; Pichlmaier, A; Reifarth, R; Wollnik, H

2005-01-01T23:59:59.000Z

326

Preparations for Muon Experiments at Fermilab  

SciTech Connect

The use of existing Fermilab facilities to provide beams for two muon experiments--the Muon to Electron Conversion Experiment (Mu2e) and the New g-2 Experiment--is under consideration. Plans are being pursued to perform these experiments following the completion of the Tevatron Collider Run II, utilizing the beam lines and storage rings used today for antiproton accumulation without considerable reconfiguration.

Syphers, M.J.; Popovic, M.; Prebys, E.; /Fermilab; Ankenbrandt, C.; /Muons Inc., Batavia

2009-05-01T23:59:59.000Z

327

Proceedings of the International Workshop on Low Energy Muon Science: LEMS`93  

SciTech Connect

This report contains papers on research with low energy muons. Topics cover fundamental electroweak physics; muonic atoms and molecules, and muon catalyzed fusion; muon spin research; and muon facilities. These papers have been indexed and cataloged separately.

Leon, M. [comp.

1994-01-01T23:59:59.000Z

328

R&D Toward a Neutrino Factory and Muon Collider  

SciTech Connect

Significant progress has been made in recent years in R&D towards a neutrino factory and muon collider. The U.S. Muon Accelerator Program (MAP) has been formed recently to expedite the R&D efforts. This paper will review the U.S. MAP R&D programs for a neutrino factory and muon collider. Muon ionization cooling research is the key element of the program. The first muon ionization cooling demonstration experiment, MICE (Muon Ionization Cooling Experiment), is under construction now at RAL (Rutherford Appleton Laboratory) in the UK. The current status of MICE will be described.

Zisman, Michael S

2011-03-20T23:59:59.000Z

329

Passive Imaging of Warhead-Like Configurations Using Cosmic-Ray Muons  

SciTech Connect

Cosmic-Muon-Based Interrogation has untapped potential for national security. This presentation describes muons-based passive interrogation techniques.

Schwellenbach, D.

2012-07-17T23:59:59.000Z

330

Muon Acceleration - RLA and FFAG  

SciTech Connect

Various acceleration schemes for muons are presented. The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and 'beam shaping' can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a non-scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain across the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. The RLAs offer very efficient usage of high gradient superconducting RF and ability to adjust path-length after each linac pass through individual return arcs with uniformly periodic FODO optics suitable for chromatic compensation of emittance dilution with sextupoles. However, they require spreaders/recombiners switchyards at both linac ends and significant total length of the arcs. The non-scaling Fixed Field Alternating Gradient (FFAG) ring combines compactness with very large chromatic acceptance (twice the injection energy) and it allows for large number of passes through the RF (at least eight, possibly as high as 15).

Alex Bogacz

2011-10-01T23:59:59.000Z

331

Muon spin depolarization in nonmagnetic metals doped with paramagnetic impurities  

Science Conference Proceedings (OSTI)

The diffusion of muons and their magnetic interactions are treated by describing the physics to be learned from experiments which measure muon depolarization in metallic hosts doped with dilute concentrations of magnetic impurities. (GHT)

Heffner, R.H.

1980-01-01T23:59:59.000Z

332

Use of dielectric material in muon accelerator RF cavities  

E-Print Network (OSTI)

The building of a muon collider is motivated by the desire to collide point-like particles while reducing the limitations imposed by synchrotron radiation. The many challenges unique to muon accelerators are derived from ...

French, Katheryn Decker

2011-01-01T23:59:59.000Z

333

Progress in Absorber R&D for Muon Cooling  

E-Print Network (OSTI)

A stored-muon-beam neutrino factory may require transverse ionization cooling of the muon beam. We describe recent progress in research and development on energy absorbers for muon-beam cooling carried out by a collaboration of university and laboratory groups.

D. M. Kaplan; E. L. Black; M. Boghosian; K. W. Cassel; R. P. Johnson; S. Geer; C. J. Johnstone; M. Popovic; S. Ishimoto; K. Yoshimura; L. Bandura; M. A. Cummings; A. Dyshkant; D. Hedin; D. Kubik; C. Darve; Y. Kuno; D. Errede; M. Haney; S. Majewski; M. Reep; D. Summers

2001-08-15T23:59:59.000Z

334

A Moment Equation Approach to a Muon Collider Cooling Lattice  

E-Print Network (OSTI)

a Muon Collider Cooling Lattice C.M. Celata, A.M. Sessler,a Muon Collider Cooling Lattice C.M. Celata and A.M. SesslerMUON COLLIDER COOLING LATTICE eM. Celata and A. M. Sessler,

Celata, C.M.; Sessler, A.M.; Lee, P.B.; Shadwick, B.A.; Wurtele, S.

2008-01-01T23:59:59.000Z

335

Higgs boson and Z physics at the first muon collider  

SciTech Connect

The potential for the Higgs boson and Z-pole physics at the first muon collider is summarized, based on the discussions at the ``Workshop on the Physics at the First Muon Collider and at the Front End of a Muon Collider``.

Demarteau, M.; Han, T.

1998-01-01T23:59:59.000Z

336

Fermilab | Muon Collider | Reports and Papers  

NLE Websites -- All DOE Office Websites (Extended Search)

Reports and Papers Reports and Papers Comprehensive Reports J. Gallardo, R. Palmer, A. Tollestrup, A. Sessler, A. Skrinsky et al., "μ+ μ- Collider: A Feasibility Study," DPF/DPB Summer Study on New Directions for High Energy Physics, Snow- mass, Colorado, 25 Jun - 12 Jul 1996, BNL - 52503, Fermilab - Conf - 96 - 092, LBNL - 38946, http://www.cap.bnl.gov/mumu/pubs/snowmass96.html C. Ankenbrandt et al.,"Status of muon collider research and development and future plans," Phys. Rev. ST Accel. Beams 2 (1999) 081001, http://prst-ab.aps.org/abstract/PRSTAB/v2/i8/e081001 M. M. Alsharo'a et al., "Recent progress in neutrino factory and muon collider research within the Muon Collaboration," Phys. Rev. ST Accel. Beams 6 (2003) 081001, http://prst-ab.aps.org/abstract/PRSTAB/v6/i8/e081001

337

Polarized photons in radiative muon capture  

E-Print Network (OSTI)

We discuss the measurement of polarized photons arising from radiative muon capture. The spectrum of left circularly polarized photons or equivalently the circular polarization of the photons emitted in radiative muon capture on hydrogen is quite sensitive to the strength of the induced pseudoscalar coupling constant $g_P$. A measurement of either of these quantities, although very difficult, might be sufficient to resolve the present puzzle resulting from the disagreement between the theoretical prediction for $g_P$ and the results of a recent experiment. This sensitivity results from the absence of left-handed radiation from the muon line and from the fact that the leading parts of the radiation from the hadronic lines, as determined from the chiral power counting rules of heavy-baryon chiral perturbation theory, all contain pion poles.

Shung-ichi Ando; Harold W. Fearing; Dong-Pil Min

2001-04-25T23:59:59.000Z

338

Complete Muon Cooling Channel Design and Simulations  

Science Conference Proceedings (OSTI)

Considerable progress has been made in developing promising subsystems for muon beam cooling channels to provide the extraordinary reduction of emittances required for an energy-frontier muon collider. However, it has not yet been demonstrated that the various proposed cooling subsystems can be consolidated into an integrated end-to-end design. Presented here are concepts to address the matching of transverse emittances between subsystems through an extension of the theoretical framework of the Helical Cooling Channel (HCC), which allows a general analytical approach to guide the transition from one set of cooling channel parameters to another.

Neuffer, D.V.; /Fermilab; Ankenbrandt, C.M.; Johnson, R.P.; Yoshikawa, C.Y.; /MUONS Inc., Batavia; Derbenev, Y.S.; Morozov, V.S.; /Jefferson Lab

2012-05-01T23:59:59.000Z

339

Complete Muon Cooling Channel Design and Simulations  

SciTech Connect

Considerable progress has been made in developing promising subsystems for muon beam cooling channels to provide the extraordinary reduction of emittances required for an energy-frontier muon collider. However, it has not yet been demonstrated that the various proposed cooling subsystems can be consolidated into an integrated end-to-end design. Presented here are concepts to address the matching of transverse emittances between subsystems through an extension of the theoretical framework of the Helical Cooling Channel (HCC), which allows a general analytical approach to guide the transition from one set of cooling channel parameters to another.

C. Y. Yoshikawa, C.M. Ankenbrandt, R.P. Johnson, Y.S. Derbenev, V.S. Morozov, D.V. Neuffer, K. Yonehara

2012-07-01T23:59:59.000Z

340

Muon interactions at 490 GeV  

DOE Green Energy (OSTI)

E665 is a new, high-energy muon scattering experiment at Fermilab. Data were taken with a 490 GeV muon beam incident on deuterium, hydrogen, and xenon targets during the 1987--88 fixed target run. These data are being analyzed with various physics objectives in mind, and a number of preliminary results have been obtained. This paper presents four of results, specifically the small {chi}{sub Bj} ratio of xenon and deuterium cross sections, inclusive hadron distributions, two jet signals, and exclusive {rho}{sup 0} production.

Schmitt, M. (Fermi National Accelerator Lab., Batavia, IL (USA) Harvard Univ., Cambridge, MA (USA))

1990-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Positron Emission Tomography/Computed Tomography in the Staging and Treatment of Anal Cancer  

SciTech Connect

Purpose: This study was intended to determine the role of PET/CT in the staging of anal cancer as a supplement to three-dimensional transanal ultrasound (TAUS) and inguinal ultrasound (US). The impact of the PET/CT on the initial stage and treatment plan proposed by TAUS/US was assessed. Methods and Materials: Ninety-five (95) patients referred to our clinic between July 1, 2005, and December 31, 2009, were retrospectively reviewed. All patients had biopsy-proven primary squamous cell cancer of the anal canal. There were 65 females (68%) and 30 males (32%), and the median age was 58 years (range, 35-88 years). Six (6%) of the patients were HIV positive. All patients were staged with TAUS/US and PET/CT. Results: Twenty-eight (28) patients were diagnosed with suspicious perirectal node metastases. TAUS visualized 24 of these, whereas PET/CT detected 15. Suspicious inguinal nodes were visualized on either US or PET/CT in 41 patients. Seventeen (17) of these had confirmed malignant disease on biopsy, and 15 had confirmed benign disease. All 17 patients (100%) with malignant inguinal nodes were diagnosed by PET/CT, whereas US identified 16 (94%). Ten patients were diagnosed with suspicious inguinal nodes on PET/CT that had not been seen on US. One of these was malignant, three were benign, and six were not biopsied. PET/CT diagnosed eight metastatic sites, whereas TAUS/US diagnosed three. PET/CT discovered three of the five synchronous cancers seen in this study. PET/CT upstaged the disease in 14% of the cases and changed the treatment plan proposed by TAUS/US in 17%. Conclusion: PET/CT has great potential influence on the staging and treatment of anal cancer. TAUS is important in the staging of the primary tumor and N1-stage, whereas PET/CT seems necessary for the N2/3-stage, the M-stage and synchronous cancers.

Sveistrup, Joen, E-mail: joensveistrup@hotmail.com [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); Loft, Annika [PET and Cyclotron Unit, Department of Clinical Physiology and Nuclear Medicine, Centre of Diagnostic Investigations, Rigshospitalet, Copenhagen (Denmark); Berthelsen, Anne Kiil [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark); PET and Cyclotron Unit, Department of Clinical Physiology and Nuclear Medicine, Centre of Diagnostic Investigations, Rigshospitalet, Copenhagen (Denmark); Henriksen, Birthe Merete; Nielsen, Michael Bachmann [Department of Radiology, Section of Ultrasound X4123, Rigshospitalet, Copenhagen (Denmark); Engelholm, Svend Aage [Department of Radiation Oncology, Rigshospitalet, Copenhagen (Denmark)

2012-05-01T23:59:59.000Z

342

Alpha-muon sticking and chaos in muon-catalysed "in flight" d-t fusion  

E-Print Network (OSTI)

We discuss the alpha-muon sticking coefficient in the muon-catalysed ``in flight" d-t fusion in the framework of the Constrained Molecular Dynamics model. Especially the influence of muonic chaotic dynamics on the sticking coefficient is brought into focus. The chaotic motion of the muon affects not only the fusion cross section but also the $\\mu-\\alpha$ sticking coefficient. Chaotic systems lead to larger enhancements with respect to regular systems because of the reduction of the tunneling region. Moreover they give smaller sticking probabilities than those of regular events. By utilizing a characteristic of the chaotic dynamics one can avoid losing the muon in the $\\mu$CF cycle. We propose the application of the so-called ``microwave ionization of a Rydberg atom" to the present case which could lead to the enhancement of the reactivation process by using X-rays.

Sachie Kimura; Aldo Bonasera

2006-05-24T23:59:59.000Z

343

Multi-muon events at CDF  

E-Print Network (OSTI)

We report a study of multi-muon events produced at the Fermilab Tevatron collider and recorded by the CDF II detector. In a data set acquired with a dedicated dimuon trigger and corresponding to an integrated luminosity of 2100 pb$^{-1}$, we isolate a significant sample of events in which at least one of the identified muons has large impact parameter and is produced outside the beam pipe of radius 1.5 cm. We are unable to fully account for the number and properties of the events through standard model processes in conjunction with our current understanding of the CDF II detector, trigger and event reconstruction. Several topological and kinematic properties of these events are also presented. In contrast, the production cross section and kinematics of events in which both muon candidates are produced inside the beam pipe are successfully modeled by known QCD processes which include heavy flavor production. The presence of these anomalous multi-muon events offers a plausible resolution to long-standing inconsistencies related to $b\\bar{b}$ production and decay.

F. Ptochos

2009-07-01T23:59:59.000Z

344

Multi-muon events at CDF  

SciTech Connect

We report a study of multi-muon events produced at the Fermilab Tevatron collider and recorded by the CDF II detector. In a data set acquired with a dedicated dimuon trigger and corresponding to an integrated luminosity of 2100 pb{sup -1}, we isolate a significant sample of events in which at least one of the identified muons has large impact parameter and is produced outside the beam pipe of radius 1.5 cm. We are unable to fully account for the number and properties of the events through standard model processes in conjunction with our current understanding of the CDF II detector, trigger and event reconstruction. Several topological and kinematic properties of these events are also presented. In contrast, the production cross section and kinematics of events in which both muon candidates are produced inside the beam pipe are successfully modeled by known QCD processes which include heavy flavor production. The presence of these anomalous multi-muon events offers a plausible resolution to long-standing inconsistencies related to b{bar b} production and decay.

Ptochos, F.; /Cyprus U.

2009-07-01T23:59:59.000Z

345

Muon Collider Machine-Detector Interface  

SciTech Connect

In order to realize the high physics potential of a Muon Collider (MC) a high luminosity of {mu}{sup +}{mu}{sup -}-collisions at the Interaction Point (IP) in the TeV range must be achieved ({approx}10{sup 34} cm{sup -2}s{sup -1}). To reach this goal, a number of demanding requirements on the collider optics and the IR hardware - arising from the short muon lifetime and from relatively large values of the transverse emittance and momentum spread in muon beams that can realistically be obtained with ionization cooling should be satisfied. These requirements are aggravated by limitations on the quadrupole gradients as well as by the necessity to protect superconducting magnets and collider detectors from muon decay products. The overall detector performance in this domain is strongly dependent on the background particle rates in various sub-detectors. The deleterious effects of the background and radiation environment produced by the beam in the ring are very important issues in the Interaction Region (IR), detector and Machine-Detector Interface (MDI) designs. This report is based on studies presented very recently.

Mokhov, Nikolai V.; /Fermilab

2011-08-01T23:59:59.000Z

346

Helical Muon Beam Cooling Channel Engineering Design  

SciTech Connect

The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; /Fermilab; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

2012-05-01T23:59:59.000Z

347

The ATLAS Muon Trigger vertical slice at LHC startup  

E-Print Network (OSTI)

The ATLAS trigger system has a three-levels structure, implemented to retain interesting physics events, here described for the muon case ("Muon Vertical Slice"). The first level, implemented in a custom hardware, uses measurements from the trigger chambers of the Muon Spectrometer to select muons with high transverse momentum and defines a Region of Interest (RoI) in the detector. RoIs are then processed by a second trigger level, in which fast algorithms run on an online software architecture. Full granularity information from precision chambers is accessed inside RoIs. A third trigger level (Event Filter), using offline-like algorithms and accessing the full event, provide the best possible muon reconstruction/identification and finally confirm or discard the trigger hypothesis formed at earlier levels. Implementation and performance of the full muon trigger slice, together with first events triggered with LHC beams on, are presented.

Grancagnolo, Sergio

2009-01-01T23:59:59.000Z

348

Performance study of the level-1 di-muon trigger  

E-Print Network (OSTI)

An event with two muons in the final state is a distinctive signal and can be triggered efficiently with the use of the level-1 di-muon trigger. Nevertheless triggering is still an issue if these muon tracks are fairly soft and fake di-muon triggers originating from muons that traverse more than one region of the trigger chambers increase the trigger rate. It is important to provide an acceptable trigger rate, while keeping high trigger efficiency to study low-pt $B$-physics such as rare $B$ hadron decays or CP violation in the $B$-events, especially in a multi-purpose experiment like ATLAS. In this note, the level-1 di-muon trigger and its expected performance are described.

The ATLAS Collaboration

2009-01-01T23:59:59.000Z

349

High field solenoids for muon cooling  

DOE Green Energy (OSTI)

The proposed cooling system for the muon collider will consist of a 200 meter long line of alternating field straight solenoids interspersed with bent solenoids. The muons are cooled in all directions using a 400 mm long section liquid hydrogen at high field. The muons are accelerated in the forward direction by about 900 mm long, 805 MHz RF cavities in a gradient field that goes from 6 T to -6 T in about 300 mm. The high field section in the channel starts out at an induction of about 2 T in the hydrogen. As the muons proceed down the cooling channel, the induction in the liquid hydrogen section increases to inductions as high as 30 T. The diameter of the liquid hydrogen section starts at 750 mm when the induction is 2 T. As the induction in the cooling section goes up, the diameter of the liquid hydrogen section decreases. When the high field induction is 30 T, the diameter of the liquid hydrogen section is about 80 mm. When the high field solenoid induction is below 8.5 T or 9T, niobium titanium coils are proposed for generating .the magnetic field. Above 8.5 T or 9 T to about 20 T, graded niobium tin and niobium titanium coils would be used at temperatures down to 1.8 K. Above 20 T, a graded bybrid magnet system is proposed, where the high field magnet section (above 20 T) is either a conventional water cooled coil section or a water cooled Bitter type coil. Two types of superconducting coils have been studied. They include; epoxy impregnated intrinsically stable coils, and cable in conduit conductor (CICC) coils with helium in the conduit.

Green, M.A.; Eyssa, Y.; Kenny, S.; Miller, J.R.; Prestemon, S.

1999-09-08T23:59:59.000Z

350

Search for muon neutrinos from Gamma-Ray Bursts with the IceCube neutrino telescope  

E-Print Network (OSTI)

the University of California. Search for muon neutrinos fromSearch for muon neutrinos from Gamma-Ray Bursts with theWe present the results of searches for high-energy muon

Abbasi, R.

2010-01-01T23:59:59.000Z

351

Muon Application to Advanced Bio- and Nano-Sciences  

SciTech Connect

Among present and future applications of the muon to various fields of sciences, there are several examples where research accomplishments can only be done by using muons. Here we would like to explain the selected two examples representing bio- and nano-sciences, namely, muon spin imaging of human brain for new brain function studies and muonium spin-exchange scattering spectroscopy for the development of spintronics materials.

Nagamine, Kanetada [Muon Science Laboratory, KEK, Tsukuba, Ibaraki, 305-0081 (Japan); Atomic Physics Laboratory, RIKEN, Wako, Saitama, 351-0198 (Japan); Department of Physics and Astronomy, University of California, Riverside, CA92521 (United States)

2008-02-21T23:59:59.000Z

352

Jet production in muon scattering at Fermilab E665  

SciTech Connect

Measurements of multi-jet production rates from Muon-Nucleon and Muon-Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Nucleon deep-inelastic scattering are compared to Monte Carlo model predictions. Preliminary results from jet production on heavy targets, in the shadowing region, show a higher suppression of two-forward jets as compared to one-forward jet production.

Salgado, C.W.; E665 Collaboration

1993-11-01T23:59:59.000Z

353

Jack Steinberger and the Muon-Neutrino  

Office of Scientific and Technical Information (OSTI)

Jack Steinberger and the Muon-Neutrino Resources with Additional Information Jack Steinberger Photograph by Harry Sticker, courtesy AIP Emilio Segre Visual Archives, Physics Today Collection In an interview, Jack Steinberger spoke about his 1988 Nobel Prize winning research. He states "I did an experiment, together with several other people at Brookhaven National Laboratory ... which showed that there is a second kind of neutrino. The neutrino has elementary particles. Elementary particles exist in families of particles ... . At the time, the elementary particles which were involved were the electrons and the neutrino. ... [W]e required the [BNL] accelerator, which was the effort of very many people, ... and this allowed [us] to make a beam of these neutrinos, and we were able to convince ourselves that these neutrinos were not the same kind of neutrinos as those which had been seen before. They were associated with not electrons, but with something called [muons]. So we were able to understand that there is a different neutrino associated with the [muon] than with the electron.

354

Advances in Beam Cooling for Muon Colliders  

DOE Green Energy (OSTI)

A six-dimensional (6D) ionization cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas is the basis for the latest plans for muon colliders. This helical cooling channel (HCC) has solenoidal, helical dipole, and helical quadrupole magnetic fields, where emittance exchange is achieved by using a continuous homogeneous absorber. Momentum-dependent path length differences in the dense hydrogen energy absorber provide the required correlation between momentum and ionization loss to accomplish longitudinal cooling. Recent studies of an 800 MHz RF cavity pressurized with hydrogen, as would be used in this application, show that the maximum gradient is not limited by a large external magnetic field, unlike vacuum cavities. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, will be employed to further reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that is being developed for an exceptional 6D cooling demonstration experiment. The status of the designs, simulations, and tests of the cooling components for a high luminosity, low emittance muon collider will be reviewed.

R.P. Johnson, Y.S. Derbenev

2006-09-01T23:59:59.000Z

355

Hydrogen Cryostat for Muon Beam Cooling  

DOE Green Energy (OSTI)

The project was to develop cryostat designs that could be used for muon beam cooling channels where hydrogen would circulate through refrigerators and the beam-cooling channel to simultaneously refrigerate 1) high-temperature-superconductor (HTS) magnet coils, 2) cold copper RF cavities, and 3) the hydrogen that is heated by the muon beam. In an application where a large amount of hydrogen is naturally present because it is the optimum ionization cooling material, it was reasonable to explore its use with HTS magnets and cold, but not superconducting, RF cavities. In this project we developed computer programs for simulations and analysis and conducted experimental programs to examine the parameters and technological limitations of the materials and designs of Helical Cooling Channel (HCC) components (magnet conductor, RF cavities, absorber windows, heat transport, energy absorber, and refrigerant).The project showed that although a hydrogen cryostat is not the optimum solution for muon ionization cooling channels, the studies of the cooling channel components that define the cryostat requirements led to fundamental advances. In particular, two new lines of promising development were opened up, regarding very high field HTS magnets and the HS concept, that have led to new proposals and funded projects.

Johnson, Rolland P.

2008-05-07T23:59:59.000Z

356

Ionization cooling in the muon collider  

SciTech Connect

The muon beams in a high luminosity muon collider are produced with a very large emittance. The process of ionization cooling offers a method for reducing the 6-dimensional normalized emittance of the beam by a factor of {approx} 10{sup 6}. A simple analytic theory has been developed that demonstrates the dependence of the net cooling on various experimental parameters. The simple theory has been checked and realistic arrangements have been examined using Monte Carlo simulations. Transverse cooling of the initial beam can be achieved using passive Li absorbers in a FOFO lattice. The last factor of 10 in transverse cooling probably requires the use of current-carrying Li lenses. Efficient longitudinal cooling requires the use of wedge shaped absorbers in a dispersive section of the beam line. An example, multi-stage cooling scenario has been developed that meets the requirements of the muon collider. Preliminary designs have been made of solenoids for use in the FOFO lattice and of solenoids and dipoles for use in the emittance exchange sections. Detailed simulation work, farther optimization, and preparations for experimental demonstrations of critical components are currently in progress.

Fernow, R.C.; Gallardo, J.C.; Kirk, H.G.; Palmer, R.B. [and others

1996-10-01T23:59:59.000Z

357

Recent Innovations in Muon Beam Cooling  

DOE Green Energy (OSTI)

Eight new ideas are being developed under SBIR/STTR grants to cool muon beams for colliders, neutrino factories, and muon experiments. Analytical and simulation studies have confirmed that a six-dimensional (6D) cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas can provide effective beam cooling. This helical cooling channel (HCC) has solenoidal, helical dipole, helical quadrupole, and helical sextupole magnetic fields to generate emittance exchange and achieve 6D emittance reduction of over 3 orders of magnitude in a 100 m segment. Four such sequential HCC segments, where the RF frequencies are increased and transverse physical dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost five orders of magnitude. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, then can be employed to reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that can be used as MANX, an exceptional 6D cooling demonstration experiment.

Rolland P. Johnson; Mohammad Alsharo'a; Charles Ankenbrandt; Emanuela Barzi; Kevin Beard; S. Alex Bogacz; Yaroslav Derbenev; Licia Del Frate; Ivan Gonin; Pierrick M. Hanlet; Robert Hartline; Daniel M. Kaplan; Moyses Kuchnir; Alfred Moretti; David Neuffer; Kevin Paul; Milorad Popovic; Thomas J. Roberts; Gennady Romanov; Daniele Turrioni; Victor Yarba; and Katsuya Yonehara

2006-03-01T23:59:59.000Z

358

Toroidal magnetic detector for high resolution measurement of muon momenta  

DOE Patents (OSTI)

A muon detector system including central and end air-core superconducting toroids and muon detectors enclosing a central calorimeter/detector are described in this paper. Muon detectors are positioned outside of toroids and all muon trajectory measurements are made in a nonmagnetic environment. Internal support for each magnet structure is provided by sheets, located at frequent and regularly spaced azimuthal planes, which interconnect the structural walls of the toroidal magnets. In a preferred embodiment, the shape of the toroidal magnet volume is adjusted to provide constant resolution over a wide range of rapidity.

Bonanos, P.

1990-11-30T23:59:59.000Z

359

Toroidal magnetic detector for high resolution measurement of muon momenta  

DOE Patents (OSTI)

A muon detector system including central and end air-core superconducting toroids and muon detectors enclosing a central calorimeter/detector. Muon detectors are positioned outside of toroids and all muon trajectory measurements are made in a nonmagnetic environment. Internal support for each magnet structure is provided by sheets, located at frequent and regularly spaced azimuthal planes, which interconnect the structural walls of the toroidal magnets. In a preferred embodiment, the shape of the toroidal magnet volume is adjusted to provide constant resolution over a wide range of rapidity. 4 figs.

Bonanos, P.

1992-01-07T23:59:59.000Z

360

RELIABILITY CONSIDERATIONS OF ELECTRONICS COMPONENTS FOR THE DEEP UNDERWATER MUON AND NEUTRINO DETECTION SYSTEM  

E-Print Network (OSTI)

Considerations for the Dtep Underwater Muon and NeutrinoPresented at the Deep Underwater Huon and Neutrino DetectionCOMPONENTS FOR THE DEEP UNDERWATER MUON AND NEUTRINO

Leskovar, B.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

The intergration of liquid and solid muon absorbers into afocusing magnet of a muon cooling channel  

DOE Green Energy (OSTI)

This report describes how one can integrate the muonabsorber with the focusing coils of a SFOFO muon cooling channel [1]. Theabsorber material must be a low Z material that reduces the muon momentumwith minimum scattering. The best materials to use for muon ionizationcooling absorbers are hydrogen, helium, lithium hydride, lithium, andberyllium. Hydrogen or helium in an absorber would normally be in theliquid state. Lithium hydride, lithium, and beryllium would normally bein the solid state. This report limits the absorber materials discussedto hydrogen, helium, lithium, and beryllium. In order to achieve the samelevel of ionization cooling with a solid absorber as a liquid hydrogenabsorber, the beta of the muon beam must be reduced more than a factor oftwo. This affects both the designs of the absorber and the magnet aroundit. Reducing the beam beta reduces the momentum acceptance of thechannel. Integration of a liquid hydrogen absorber and solid absorberswith a superconducting focusing solenoid is discussed. The choice ofabsorber material affects the design of the superconducting focusingmagnet and the superconductor that is used to generate the magneticfield.

Green, M.A.; Black, E.L.; Cummings, M.A.; Kaplan, D.M.; Ishimoto,S.; Cobb, J.H.; Lau, W.; Yang, S.; Palmer, R.B.

2003-05-01T23:59:59.000Z

362

Atmospheric Muon Flux at Sea Level, Underground, and Underwater  

E-Print Network (OSTI)

The vertical sea-level muon spectrum at energies above 1 GeV and the underground/underwater muon intensities at depths up to 18 km w.e. are calculated. The results are particularly collated with a great body of the ground-level, underground, and underwater muon data. In the hadron-cascade calculations, the growth with energy of inelastic cross sections and pion, kaon, and nucleon generation in pion-nucleus collisions are taken into account. For evaluating the prompt muon contribution to the muon flux, we apply two phenomenological approaches to the charm production problem: the recombination quark-parton model and the quark-gluon string model. To solve the muon transport equation at large depths of homogeneous medium, a semi-analytical method is used. The simple fitting formulas describing our numerical results are given. Our analysis shows that, at depths up to 6-7 km w. e., essentially all underground data on the muon intensity correlate with each other and with predicted depth-intensity relation for conventional muons to within 10%. However, the high-energy sea-level data as well as the data at large depths are contradictory and cannot be quantitatively decribed by a single nuclear-cascade model.

E. V. Bugaev; A. Misaki; V. A. Naumov; T. S. Sinegovskaya; S. I. Sinegovsky; N. Takahashi

1998-03-30T23:59:59.000Z

363

Chromaticity correction for a muon collider optics  

Science Conference Proceedings (OSTI)

Muon Collider (MC) is a promising candidate for the next energy frontier machine. However, in order to obtain peak luminosity in the 10{sup 34} cm{sup 2}s{sup -1} range the collider lattice designmust satisfy a number of stringent requirements. In particular the expected large momentum spread of the muon beam and the very small {beta}* call for a careful correction of the chromatic effects. Here we present a particular solution for the interaction region (IR) optics whose distinctive feature is a three-sextupole local chromatic correction scheme. The scheme may be applied to other future machines where chromatic effects are expected to be large. The expected large muon energy spread requires the optics to be stable over a wide range of momenta whereas the required luminosity calls for {beta}* in the mm range. To avoid luminosity degradation due to hour-glass effect, the bunch length must be comparatively small. To keep the needed RF voltage within feasible limits the momentum compaction factor must be small over the wide range of momenta. A low {beta}* means high sensitivity to alignment and field errors of the Interaction Region (IR) quadrupoles and large chromatic effects which limit the momentum range of optics stability and require strong correction sextupoles, which eventually limit the Dynamic Aperture (DA). Finally, the ring circumference should be as small as possible, luminosity being inversely proportional to the collider length. A promising solution for a 1.5 TeV center of mass energy MC with {beta}* = 1 m in both planes has been proposed. This {beta}* value has been chosen as a compromise between luminosity and feasibility based on the magnet design and energy deposition considerations. The proposed solution for the IR optics together with a new flexible momentum compaction arc cell design allows to satisfy all requirements and is relatively insensitive to the beam-beam effect.

Alexahin, Y.; Gianfelice-Wendt, E.; Kapin, V.; /Fermilab

2011-03-01T23:59:59.000Z

364

Effect of muon-nuclear inelastic scattering on high-energy atmospheric muon spectrum at large depth underwater  

E-Print Network (OSTI)

The energy spectra of hadron cascade showers produced by the cosmic ray muons travelling through water as well as the muon energy spectra underwater at the depth up to 4 km are calculated with two models of muon inelastic scattering on nuclei, the recent hybrid model (two-component, 2C) and the well-known generalized ector-meson-dominance model for the comparison. The 2C model involves photonuclear interactions at low and moderate virtualities as well as the hard scattering including the weak neutral current processes. For the muon scattering off nuclei substantial uclear effects, shadowing, nuclear binding and Fermi motion of nucleons are taken into account. It is shown that deep nderwater muon energy spectrum calculated with the 2C model are noticeably distorted at energies above 100 TeV as compared to that obtained with the GVMD model.

Sinegovsky, S I; Lokhtin, K S; Takahashi, N

2007-01-01T23:59:59.000Z

365

Effect of muon-nuclear inelastic scattering on high-energy atmospheric muon spectrum at large depth underwater  

E-Print Network (OSTI)

The energy spectra of hadron cascade showers produced by the cosmic ray muons travelling through water as well as the muon energy spectra underwater at the depth up to 4 km are calculated with two models of muon inelastic scattering on nuclei, the recent hybrid model (two-component, 2C) and the well-known generalized ector-meson-dominance model for the comparison. The 2C model involves photonuclear interactions at low and moderate virtualities as well as the hard scattering including the weak neutral current processes. For the muon scattering off nuclei substantial uclear effects, shadowing, nuclear binding and Fermi motion of nucleons are taken into account. It is shown that deep nderwater muon energy spectrum calculated with the 2C model are noticeably distorted at energies above 100 TeV as compared to that obtained with the GVMD model.

S. I. Sinegovsky; A. Misaki; K. S. Lokhtin; N. Takahashi

2007-12-24T23:59:59.000Z

366

Extended Air Showers and Muon Interactions  

E-Print Network (OSTI)

The objective of this work is to report on the influence of muon interactions on the development of air showers initiated by astroparticles. We make a comparative study of the different theoretical approaches to muon bremsstrahlung and muonic pair production interactions. A detailed algorithm that includes all the relevant characteristics of such processes has been implemented in the AIRES air shower simulation system. We have simulated ultra high energy showers in different conditions in order to measure the influence of these muonic electromagnetic interactions. We have found that during the late stages of the shower development (well beyond the shower maximum) many global observables are significantly modified in relative terms when the mentioned interactions are taken into account. This is most evident in the case of the electromagnetic component of very inclined showers. On the other hand, our simulations indicate that the studied processes do not induce significant changes either in the position of the shower maximum or the structure of the shower front surface.

A. N. Cillis; S. J. Sciutto

2000-10-24T23:59:59.000Z

367

EPIC Muon Cooling Simulations using COSY INFINITY  

SciTech Connect

Next gen­er­a­tion mag­net sys­tems need­ed for cool­ing chan­nels in both neu­tri­no fac­to­ries and muon col­lid­ers will be in­no­va­tive and com­pli­cat­ed. De­sign­ing, sim­u­lat­ing and op­ti­miz­ing these sys­tems is a chal­lenge. Using COSY IN­FIN­I­TY, a dif­fer­en­tial al­ge­bra-based code, to sim­u­late com­pli­cat­ed el­e­ments can allow the com­pu­ta­tion and cor­rec­tion of a va­ri­ety of high­er order ef­fects, such as spher­i­cal and chro­mat­ic aber­ra­tions, that are dif­fi­cult to ad­dress with other sim­u­la­tion tools. As an ex­am­ple, a he­li­cal dipole mag­net has been im­ple­ment­ed and sim­u­lat­ed, and the per­for­mance of an epicyclic para­met­ric ion­iza­tion cool­ing sys­tem for muons is stud­ied and com­pared to sim­u­la­tions made using G4Beam­line, a GEAN­T4 toolk­it.

J.A. Maloney, B. Erdelyi, A. Afanasev, R.P. Johnson, S.A. Bogacz, Y.S. Derbenev, V.S. Morozov

2011-03-01T23:59:59.000Z

368

Positive muon and the positron as probes of defects  

SciTech Connect

The positive muon and the positron are each being used nowadays to investigate defects in condensed matter. A brief summary of the experimental methods employed with each particle is given in this paper. Similarities and differences between the behavior of the two leptons when implanted in consensed matter are pointed out, and by means of a comparison between muon and positron data in Al it is shown that the combination of muon and positron experiments can serve as a useful new probe of defects in solids.

Lynn, K G

1980-01-01T23:59:59.000Z

369

Helical FOFO snake for 6D ionization cooling of muons  

DOE Green Energy (OSTI)

A channel for 6D ionization cooling of muons is described which consists of periodically inclined solenoids of alternating polarity, liquid hydrogen absorbers placed inside solenoids and RF cavities between them. Important feature of such channel (called Helical FOFO snake) is that it can cool simultaneously muons of both signs. Theoretical considerations as well as results of simulations with G4Beamline are presented which show that 200MHz HFOFO snake has sufficient acceptance to be used for initial 6D cooling in muon colliders and neutrino factories.

Alexahin, Y.; /Fermilab

2009-10-01T23:59:59.000Z

370

Novel Muon Beam Facilities for Project X at Fermilab  

SciTech Connect

Innovative muon beam concepts for intensity-frontier experiments such as muon-to-electron conversion are described. Elaborating upon a previous single-beam idea, we have developed a design concept for a system to generate four high quality, low-energy muon beams (two of each sign) from a single beam of protons. As a first step, the production of pions by 1 and 3 GeV protons from the proposed Project X linac at Fermilab is being simulated and compared with the 8-GeV results from the previous study.

Neuffer, D.V.; /Fermilab; Ankenbrandt, C.M.; Abrams, R.; Roberts, T.J.; Yoshikawa, C.Y.; /MUONS Inc., Batavia

2012-05-01T23:59:59.000Z

371

Recent Innovations in Muon Beam Cooling and Prospects for Muon Colliders  

DOE Green Energy (OSTI)

A six-dimensional(6D)cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas* is used to achieve the small transverse emittances demanded by a high-luminosity muon collider. This helical cooling channel**(HCC) has solenoidal, helical dipole, and helical quadrupole magnetic fields to generate emittance exchange. Simulations verify the analytic predictions and have shown a 6D emittance reduction of over 3 orders of magnitude in a 100 m HCC segment. Using three such sequential HCC segments, where the RF frequencies are increased and transverse dimensions reduced as the beams become cooler, implies a 6D emittance reduction of almost six orders of magnitude. After this, two new post-cooling ideas can be employed to reduce transverse emittances to one or two mm-mr, which allows high luminosity with fewer muons than previously imagined. In this report we discuss the status of and the plans for the HCC simulation and engineering efforts. We also describe the new post-cooling ideas and comment on the prospects for a Higgs factory or energy frontier muon collider using existing laboratory infrastructure.

R.P. Johnson; M. Alsharo'a; P.M. Hanlet; R. E. Hartline; M. Kuchnir; K. Paul; T.J. Roberts; C.M. Ankenbrandt; E. Barzi; L. DelFrate; I.G. Gonin; A. Moretti; D.V. Neuffer; M. Popovic; G. Romanov; D. Turrioni; V. Yarba; K. Beard; S.A. Bogacz; Y.S. Derbenev; D.M. Kaplan; K. Yonehara

2005-05-16T23:59:59.000Z

372

Muon Acceleration in Cosmic-ray Sources  

E-Print Network (OSTI)

Many models of ultra-high energy cosmic-ray production involve acceleration in linear accelerators located in Gamma-Ray Bursts magnetars, or other sources. These source models require very high accelerating gradients, $10^{13}$ keV/cm, with the minimum gradient set by the length of the source. At gradients above 1.6 keV/cm, muons produced by hadronic interactions undergo significant acceleration before they decay. This acceleration hardens the neutrino energy spectrum and greatly increases the high-energy neutrino flux. We rule out many models of linear acceleration, setting strong constraints on plasma wakefield accelerators and on models for sources like Gamma Ray Bursts and magnetars.

Spencer R. Klein; Rune Mikkelsen; Julia K. Becker Tjus

2012-08-09T23:59:59.000Z

373

New results for rare muon decays  

Science Conference Proceedings (OSTI)

Branching-ratio limits obtained with the Crystal Box detector are presented for the rare muon decays ..mu.. ..-->.. eee, ..mu.. ..-->.. e..gamma.., and ..mu.. ..-->.. e..gamma gamma... These decays, which violate the conservation of separate lepton-family numbers, are expected to occur in many extensions to the standard model. We found no candidates for the decay ..mu.. ..-->.. eee, yielding an upper limit for the branching ratio of B/sub ..mu..3e/ .. e..gamma.. candidates yields an upper limit of B/sub ..mu..e..gamma../ .. e..gamma gamma.. candidates gives an upper limit of B/sub ..mu..e..gamma gamma../ < 7.2 x 10/sup -11/. These results strengthen the constraints on models that allow transitions between lepton families.

Mischke, R.E.; Bolton, R.D.; Bowman, J.D.; Cooper, M.D.; Frank, J.S.; Hallin, A.L.; Heusi, P.A.; Hoffman, C.M.; Hogan, G.E.; Mariam, F.G.

1986-01-01T23:59:59.000Z

374

Ordinary Muon Capture in Hydrogen Reexamined  

E-Print Network (OSTI)

The rate of muon capture in a muonic hydrogen atom is calculated in heavy-nucleon chiral perturbation theory up to next-to-next-to leading order. To this order, we present the systematic evaluation of all the corrections due to the QED and electroweak radiative corrections and the proton-size effect. Since the low-energy constants involved can be determined from other independent sources of information, the theory has predictive power. For the hyperfine-singlet $\\mu p$ capture rate $\\Gamma_0$, our calculation gives $\\Gamma_0=710 \\,\\pm 5\\,s^{-1}$, which is in excellent agreement with the experimental value obtained in a recent high-precision measurement by the MuCap Collaboration.

U. Raha; F. Myhrer; K. Kubodera

2013-03-25T23:59:59.000Z

375

When will we know a muon collider is feasible? Status and directions of muon accelerator R&D  

E-Print Network (OSTI)

Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture, accelerate and collide high intensity beams of muons. At present, a high-luminosity multi-TeV muon collider presents a viable option for the next generation lepton-lepton collider, which is believed to be needed to fully explore high energy physics in the era following the LHC discoveries. This article briefly reviews the status of the accelerator R&D, addresses the question of the feasibility of a Muon Collider, what needs to be done to prove it and presents projected timeline of the project.

Vladimir Shiltsev

2010-03-16T23:59:59.000Z

376

Melvin Schwartz and the Discovery of the Muon Neutrino  

NLE Websites -- All DOE Office Websites (Extended Search)

Melvin Schwartz and the Discovery of the Muon Neutrino Melvin Schwartz and the Discovery of the Muon Neutrino Resources with Additional Information Melvin Schwartz Courtesy Brookhaven National Laboratory Melvin Schwartz was the co-winner of the 1988 Nobel Prize in Physics "for the neutrino beam method and the demonstration of the doublet structure of the leptons through the discovery of the muon neutrino". 'In 1962, Schwartz, with Leon Lederman and Jack Steinberger ... discovered the muon neutrino at the Alternating Gradient Synchrotron (AGS), the then brand-new accelerator at the U.S. Department of Energy's Brookhaven National Laboratory. ... First coming to Brookhaven in 1955, Schwartz performed his Ph.D. thesis research through 1956 at the Laboratory's first accelerator, the Cosmotron. While finishing his thesis, he was employed by the Laboratory from 1956-58.

377

Neutrino Factory and Muon Collider R&D  

E-Print Network (OSTI)

European, Japanese, and US Neutrino Factory designs are presented. The main R&D issues and associated R&D programs, future prospects, and the additional issues that must be addressed to produce a viable Muon Collider design, are discussed.

Steve Geer

2001-11-05T23:59:59.000Z

378

Asymmetry of Charge Ratio for Low Energetic Muons  

Science Conference Proceedings (OSTI)

The WILLI calorimeter, installed in NIPNE Bucharest, is operated since several years for measuring charge ratio of atmospheric muons at low energies (Egeomagnetic field and also on features of the hadronic interaction.

Mitrica, Bogdan [National Institute for Physics and Nuclear Engineering, Horia Hulubei, Bucharest (Romania)

2008-01-24T23:59:59.000Z

379

Commissioning of the ATLAS Muon Spectrometer with Cosmic Rays  

E-Print Network (OSTI)

The ATLAS detector at the Large Hadron Collider has collected several hundred million cosmic ray events during 2008 and 2009. These data were used to commission the Muon Spectrometer and to study the performance of the trigger and tracking chambers, their alignment, the detector control system, the data acquisition and the analysis programs. We present the performance in the relevant parameters that determine the quality of the muon measurement. We discuss the single element efficiency, resolution and noise rates, the calibration method of the detector response and of the alignment system, the track reconstruction efficiency and the momentum measurement. The results show that the detector is close to the design performance and that the Muon Spectrometer is ready to detect muons produced in high energy proton-proton collisions.

The ATLAS Collaboration

2010-06-22T23:59:59.000Z

380

On the parametrization of atmospheric muon angular flux underwater  

E-Print Network (OSTI)

The analytical expression for angular integral flux of atmospheric muons in matter with the explicit relation of its parameters with those of the sea level spectrum is obtained. The fitting formula for the sea level muon spectrum at different zenith angles for spherical atmosphere is proposed. The concrete calculations for pure water are presented. Fluctuations of muon energy losses are taken into account by means of parametrized correction factor calculated using survival probabilities resulted from Monte Carlo simulations. Parametrizations of all continuous energy losses are obtained with using the most recent expressions for muon interaction cross-sections. The corresponding parametrization errors and field of method application are comprehensively discussed. The proposed formulae could be useful primarily for experimentalists processing data of arrays located deep under water or under ice.

S. I. Klimushin; E. V. Bugaev; I. A. Sokalski

2000-12-04T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
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381

Expected Muon Energy Spectra and Zenithal Distributions Deep Underwater  

E-Print Network (OSTI)

Energy spectra and zenith angle distributions of atmospheric muons are calculated for the depths of operation of large underwater neutrino telescopes. The estimation of the prompt muon contribution is performed with three approaches to charm hadroproduction: recombination quark-parton model, quark-gluon string model, and perturbative QCD based models. Calculations show that the larger are zenith angles and water thickness above the detector, the lower is the energy at which the prompt muon flux becomes equal to conventional one (``crossing energy'') . For instance, for the depth of the Baikal Neutrino Telescope and for zenith angle of 78 degrees the crossing energy is about 300 TeV, whereas it is only 8 TeV for the NESTOR depth. Nevertheless, the muon flux of the crossing energy at NESTOR depth is in order of magnitude lower in comparison with the Baikal depth.

A. Misaki; V. A. Naumov; T. S. Sinegovskaya; S. I. Sinegovsky; N. Takahashi

1999-05-19T23:59:59.000Z

382

Muon Acceleration with RLA and Non-scaling FFAG Arcs  

Science Conference Proceedings (OSTI)

Recirculating Linear Accelerators (RLA) are the most likely means to achieve the rapid acceleration of shortlived muons to multi-GeV energies required for Neutrino Factories and TeV energies required for Muon Colliders. In this paper, we present a novel return-arc optics design based on a Non Scaling Fixed Field Alternating Gradient (NS-FFAG) lattice that allows 5 and 9 GeV/c muons of both charges to be transported in the same string of magnets. The return arcs are made up of super cells with each super cell consisting of three triplets. By employing combined function magnets with dipole, quadrupole, sextupole and octupole magnetic field components, each super cell is designed to be achromatic and to have zero initial and final periodic orbit offsets for both 5 and 9 GeV/c muon momenta. This solution would reduce the number of arcs by a factor of 2, simplifying the overall design.

Vasiliy Morozov,Alex Bogacz,Dejan Trbojevic

2010-05-01T23:59:59.000Z

383

Muon transfer from hot muonic hydrogen atoms to neon  

DOE Green Energy (OSTI)

A negative muon beam has been directed on adjacent solid layers of hydrogen and neon. Three targets differing by their deuterium concentration were investigated. Muonic hydrogen atoms can drift to the neon layer where the muon is immediately transferred. The time structure of the muonic neon X-rays follows the exponential law with a disappearance rate corresponding to the one of [mu][sup [minus]p] atoms in each target. The rates [lambda][sub pp[mu

Jacot-Guillarmod, R. (Fribourg Univ. (Switzerland). Inst. de Physique); Bailey, J.M. (Liverpool Univ. (United Kingdom)); Beer, G.A.; Knowles, P.E.; Mason, G.R.; Olin, A. (Victoria Univ., BC (Canada)); Beveridge, J.L.; Marshall, G.M.; Brewer, J.H.; Forster, B.M. (British Columbia Univ., Vancouver, BC (Canada)); Huber, T.M. (Gustavus Adolphus Coll., St. Peter, MN (United States)); Kammel, P.; Zmeskal, J.

1992-01-01T23:59:59.000Z

384

The charge ratio of the atmospheric muons at low energy  

Science Conference Proceedings (OSTI)

From the nature of the muon production processes, it can be seen that the ratio of positive to negative cosmic muons has important information in both 'the atmospheric neutrino problem', and 'the hadronic interactions'. We have carried out an experiment for the measurement of the muon charge ratio in the cosmic ray flux in momentum range 0.112-0.178 GeV/c. The muon charge ratio is found to be 1.21{+-}0.01 with a mean zenith angle of 32 deg. {+-}5 deg. . From the measurements it has been obtained a zenithal angle distribution of muons as I({theta})=I(0)cos{sup n}{theta} with n=1.95{+-}0.13. An asymmetry has been observed in East-West directions because of the geomagnetic field. Meanwhile, in about the same momentum range, positive and negative muons have been studied on the basis of Monte Carlo simulations of the extensive air shower developement (Cosmic Ray Simulations for Kascade), using the Quark Gluon String model with JETs model as generator.

Bahmanabadi, M.; Samimi, J. [Department of Physics, Sharif University of Technology, P.O.Box 11365-9161, Tehran (Iran, Islamic Republic of); ALBORZ Observatory, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Sheidaei, F. [Department of Physics, Sharif University of Technology, P.O.Box 11365-9161, Tehran (Iran, Islamic Republic of); Ghomi, M. Khakian [ALBORZ Observatory, Sharif University of Technology, Tehran (Iran, Islamic Republic of)

2006-10-15T23:59:59.000Z

385

Plasma Lens for Muon and Neutrino Beams  

SciTech Connect

The plasma lens is examined as an alternate to focusing horns and solenoids for use in a neutrino or muon beam facility. The plasma lens concept is based on a combined high-energy lens/target configuration. The current is fed at electrodes located upstream and downstream from the target where pion capturing is needed. The current flows primarily in the plasma, which has a lower resistivity than the target. A second plasma lens section, with an additional current feed, follows the target to provide shaping of the plasma for optimum focusing. The plasma lens is immersed in an additional solenoid magnetic field to facilitate the plasma stability. The geometry of the plasma is shaped to provide optimal pion capture. Simulations of this plasma lens system have shown a 25% higher neutrino production than the horn system. Plasma lenses have the additional advantage of negligible pion absorption and scattering by the lens material and reduced neutrino contamination during anti-neutrino running. Results of particle simulations using plasma lens will be presented.

Kahn,S.A.; Korenev, S.; Bishai, M.; Diwan, M.; Gallardo, J.C.; Hershcovitch, A.; Johnson, B.M.

2008-06-23T23:59:59.000Z

386

Dynamic ray tracing and traveltime corrections for global seismic tomography  

Science Conference Proceedings (OSTI)

We present a dynamic ray tracing program for a spherically symmetric Earth that may be used to compute Frechet kernels for traveltime and amplitude anomalies at finite frequency. The program works for arbitrarily defined phases and background models. The numerical precisions of kinematic and dynamic ray tracing are optimized to produce traveltime errors under 0.1 s, which is well below the data uncertainty in global seismology. This tolerance level is obtained for an integration step size of about 20 km for the most common seismic phases. We also give software to compute ellipticity, crustal and topographic corrections and attenuation.

Tian Yue [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)], E-mail: ytian@princeton.edu; Hung, S.-H. [Department of Geosciences, National Taiwan University, Taipei 106, Taiwan (China); Nolet, Guust [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States); Montelli, Raffaella [ExxonMobil Upstream Research Company, P.O. Box 22189, GW03-940A, Houston, TX 77252-2189 (United States); Dahlen, F.A. [Department of Geosciences, Guyot Hall, Princeton University, NJ 08544 (United States)

2007-09-10T23:59:59.000Z

387

NIST Standards for x-ray computed tomography  

Science Conference Proceedings (OSTI)

... a standard for lung CT imaging. Staff: ... Related programs and projects: Associated products: Beta-test versions of the density and length standards ...

2013-03-26T23:59:59.000Z

388

Novel detector systems for the Positron Emission Tomography  

E-Print Network (OSTI)

In this contribution we describe a novel solution for the construction of Positron Emission Tomograph. We present the device allowing for determination of the impact position as well as time and deph of interaction of the annihilation gamma quanta. The device is comprised of scintillation chamber consisting of organic scintillators surrounding the body of the patient. We discuss two possible solutions: (i) the tomograph built out of scintillator strips, and (ii) the tomograph built out of the scintillator plates. The application of the fast scintillators will enable to take advantage of the difference between time of the registration of the annihilation quanta. The invented method will permit to use a thick layers of detector material with the possibility of measuring the depth of the gamma quantum interaction (DOI) and the determination of their time of flight (TOF), and will allow for increasing the size of the diagnostic chamber without a significant increase of costs. The method is a subject of two patent applications which are based on the techniques used in the particle physics experiments.

P. Moskal; P. Salabura; M. Silarski; J. Smyrski; J. Zdebik; M. Zieli?ski

2013-05-22T23:59:59.000Z

389

Iterative maximum-likelihood reconstruction in quantum homodyne tomography  

E-Print Network (OSTI)

I propose an iterative expectation maximization algorithm for reconstructing a quantum optical ensemble from a set of balanced homodyne measurements performed on an optical state. The algorithm applies directly to the acquired data, bypassing the intermediate step of calculating marginal distributions. The advantages of the new method are made manifest by comparing it with the traditional inverse Radon transformation technique.

A. I. Lvovsky

2003-11-14T23:59:59.000Z

390

Probing the Earth's Interior with SeismicTomography  

E-Print Network (OSTI)

for the structure is evident from the experiment by Donev et al. 1 , who studied the coordinations in an ensemble

391

Nuclear resonance tomography with a toroid cavity detector  

DOE Patents (OSTI)

A toroid cavity detection system for determining the spectral properties and distance from a fixed point for a sample using Nuclear Magnetic Resonance. The detection system consists of a toroid with a central conductor oriented along the main axis of the toroidal cylinder and perpendicular to a static uniform magnetic field oriented along the main axis of the toroid. An rf signal is inputted to the central conductor to produce a magnetic field perpendicular to the central axis of the toroid and whose field strength varies as the inverse of the radius of the toroid. The toroid cavity detection system can be used to encapsulate a sample, or the detection system can be perforated to allow a sample to flow into the detection device or to place the samples in specified sample tubes. The central conductor can also be coated to determine the spectral property of the coating and the coating thickness. The sample is then subjected to the respective magnetic fields and the responses measured to determine the desired properties.

Woelk, K.; Rathke, J.W.; Klingler, R.J.

1994-12-31T23:59:59.000Z

392

Contributions of Atom Probe Tomography to the Understanding of ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Since the introduction of the computer-controlled atom probe field ion ... to the understanding of steels have been made primarily due to its near atomic ... of the Microstructure-Property-Processing Relationships in a Series of ...

393

Quantum state tomography with fully symmetric measurements and product measurements  

SciTech Connect

We introduce random-matrix theory to study the tomographic efficiency of a wide class of measurements constructed out of weighted 2-designs, including symmetric informationally complete (SIC) probability operator measurements (POMs). In particular, we derive analytic formulas for the mean Hilbert-Schmidt distance and the mean trace distance between the estimator and the true state, which clearly show the difference between the scaling behaviors of the two error measures with the dimension of the Hilbert space. We then prove that the product SIC POMs, the multipartite analog of the SIC POMs, are optimal among all product measurements in the same sense as the SIC POMs are optimal among all joint measurements. We further show that, for bipartite systems, there is only a marginal efficiency advantage of the joint SIC POMs over the product SIC POMs. In marked contrast, for multipartite systems, the efficiency advantage of the joint SIC POMs increases exponentially with the number of parties.

Zhu Huangjun [Centre for Quantum Technologies, National University of Singapore, Singapore 117543 (Singapore); NUS Graduate School for Integrative Sciences and Engineering, Singapore 117597 (Singapore); Englert, Berthold-Georg [Centre for Quantum Technologies, National University of Singapore, Singapore 117543 (Singapore); Department of Physics, National University of Singapore, Singapore 117542 (Singapore)

2011-08-15T23:59:59.000Z

394

Measuring the Kuroshio Current with ocean acoustic tomography Naokazu Taniguchia)  

E-Print Network (OSTI)

of Engineering, Hiroshima University, Hiroshima 739-8527, Japan Chen-Fen Huangb) Institute of Oceanography, National Taiwan University, Taipei 106, Taiwan Arata Kaneko Graduate School of Engineering, Hiroshima University, Hiroshima 739-8527, Japan Cho-Teng Liu Institute of Oceanography, National Taiwan University

Frandsen, Jannette B.

395

Atom Probe Tomography Analysis of Possible Rhenium Clustering ...  

Science Conference Proceedings (OSTI)

... is distributed in the nickel lattice will help explain the fundamental reasons ... explain the rhenium-effect has been called into question. [12, 13], since it has ...

396

Pn TOMOGRAPHY AND LOCATION IN EURASIA , Scott Phillips1  

E-Print Network (OSTI)

State University2 Sponsored by National Nuclear Security Administration Office of Nonproliferation Research and Engineering Office of Defense Nuclear Nonproliferation Contract No. W-7405-ENG-36 ABSTRACT We

Rowe, Charlotte

397

Accuracy of targeted post-mortem computed tomography coronary ...  

Science Conference Proceedings (OSTI)

B. Morgan & M. J. Biggs & J. Barber & V. Raj &. J. Amoroso & F. E. Hollingbury & C. .... using a published protocol [16]. The left carotid artery was isolated at the ...

398

?A cylindrical specimen holder for electron cryo-tomography  

E-Print Network (OSTI)

. . . . . . . . . . . . . . . . . 60 3.7 Elemental maps and longitudinal EDX linescan of a carbon nanopipette 61 3.8 Transverse EDX linescan of a carbon nanopipette . . . . . . . . . . . 62 4.1 Transmission electron micrograph of a blocked carbon nanopipette tip 68 4.2 A carbon... nanopipette . . . . . . 82 4.9 Comparison of reconstructions from unprocessed and cutout images 83 4.10 Slices and line profiles from the liposome reconstruction . . . . . . . 85 4.11 Volume rendering of tomograms from a large and small angular range 87 4...

Palmer, Colin Michael

2013-03-12T23:59:59.000Z

399

Characterizing Energy Materials in 3-D Using STEM Tomography  

Science Conference Proceedings (OSTI)

... for various acquisition geometries, and the power of the technique demonstrated with applications to energy storage materials and Fischer-Tropsch catalysts.

400

Development and Implementation of 3-D, High-speed Tomography...  

NLE Websites -- All DOE Office Websites (Extended Search)

operations such as fluid-bed combustors, coal gasifiers, carbon capture processes, and Fischer-Tropsch synthesis. A dedicated 3-D ECVT for imaging fluidized-bed systems will...

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Good bones: anthropological scientific collaboration around computed tomography data  

Science Conference Proceedings (OSTI)

We report preliminary results from a socio-technical analysis of scientific collaboration, specifically a loosely connected group of physical anthropology researchers. Working from a combination of interview data and artifact analysis, we identify current ... Keywords: scientific collaboratories, virtual organizations

Andrea H. Tapia; Rosalie Ocker; Mary Beth Rosson; Bridget Blodgett

2011-02-01T23:59:59.000Z

402

The Milky Way Tomography with SDSS. 2. Stellar Metallicity  

Science Conference Proceedings (OSTI)

In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is producing a massive spectroscopic database which already contains over 280,000 stellar spectra. Using effective temperature and metallicity derived from SDSS spectra for {approx}60,000 F and G type main sequence stars (0.2 < g-r < 0.6), we develop polynomial models, reminiscent of traditional methods based on the UBV photometry, for estimating these parameters from the SDSS u-g and g-r colors. These estimators reproduce SDSS spectroscopic parameters with a root-mean-square scatter of 100 K for effective temperature, and 0.2 dex for metallicity (limited by photometric errors), which are similar to random and systematic uncertainties in spectroscopic determinations. We apply this method to a photometric catalog of coadded SDSS observations and study the photometric metallicity distribution of {approx}200,000 F and G type stars observed in 300 deg{sup 2} of high Galactic latitude sky. These deeper (g < 20.5) and photometrically precise ({approx}0.01 mag) coadded data enable an accurate measurement of the unbiased metallicity distribution for a complete volume-limited sample of stars at distances between 500 pc and 8 kpc. The metallicity distribution can be exquisitely modeled using two components with a spatially varying number ratio, that correspond to disk and halo. The best-fit number ratio of the two components is consistent with that implied by the decomposition of stellar counts profiles into exponential disk and power-law halo components by Juric et al. (2008). The two components also possess the kinematics expected for disk and halo stars. The metallicity of the halo component can be modeled as a spatially invariant Gaussian distribution with a mean of [Fe/H] = -1.46 and a standard deviation of {approx}0.3 dex. The disk metallicity distribution is non-Gaussian, with a remarkably small scatter (rms {approx}0.16 dex) and the median smoothly decreasing with distance from the plane from -0.6 at 500 pc to -0.8 beyond several kpc. Similarly, we find using proper motion measurements that a non-Gaussian rotational velocity distribution of disk stars shifts by {approx}50 km/s as the distance from the plane increases from 500 pc to several kpc. Despite this similarity, the metallicity and rotational velocity distributions of disk stars are not correlated (Kendall's {tau} = 0.017 {+-} 0.018). This absence of a correlation between metallicity and kinematics for disk stars is in a conflict with the traditional decomposition in terms of thin and thick disks, which predicts a strong correlation ({tau} = ?0.30 {+-} 0.04) at {approx}1 kpc from the mid-plane. Instead, the variation of the metallicity and rotational velocity distributions can be modeled using non-Gaussian functions that retain their shapes and only shift as the distance from the mid-plane increases. We also study the metallicity distribution using a shallower (g < 19.5) but much larger sample of close to three million stars in 8500 sq. deg. of sky included in SDSS Data Release 6. The large sky coverage enables the detection of coherent substructures in the kinematics-metallicity space, such as the Monoceros stream, which rotates faster than the LSR, and has a median metallicity of [Fe/H] = ?0.95, with an rms scatter of only {approx}0.15 dex. We extrapolate our results to the performance expected from the Large Synoptic Survey Telescope (LSST) and estimate that the LSST will obtain metallicity measurements accurate to 0.2 dex or better, with proper motion measurements accurate to {approx}0.2-0.5 mas/yr, for about 200 million F/G dwarf stars within a distance limit of {approx}100 kpc (g < 23.5).

Ivezic, Zeljko; /Washington U., Seattle; Sesar, Branimir; /Washington U., Seattle; Juric, Mario; /Princeton, Inst. Advanced Study; Bond, Nicholas; /Princeton U.; Dalcanton, Julianne; /Washington U., Seattle; Rockosi, Constance M.; /UC, Santa Cruz; Yanny, Brian; /Fermilab; Newberg, Heidi J.; /Rensselaer Poly.; Beers, Timothy C.; /Michigan State U.; Prieto, Carlos Allende; /Texas U.; Wilhelm, Ron; /Texas Tech. /Michigan State U.

2008-04-01T23:59:59.000Z

403

Ultra-high-resolution optical coherence tomography gets adaptive ...  

Eye Deformable mirror control Deformable mirror AO control Wavefront reconstruction Shack-Hartmann wavefront sensor OCT light source/laser beacon Achromatizing

404

X-Ray Phase-Contrast Tomography for Quantitative ...  

Science Conference Proceedings (OSTI)

... in a range of areas including analysis of self-healing polymers, visualisation of fluids in porous materials, .... Tool Failure Criteria while Drilling Titanium Alloys.

405

Correlation of Porosity Detected by Computed Tomography and ...  

Science Conference Proceedings (OSTI)

How to Control Strength and Grain Structure of 304L Stainless Steel during Forging · Improved ... Process Modeling and Reduction of Copper Loss in Smelting Slag ... Use of Polymeric Residues from the Footwear Industry in Layers of Asphalt ...

406

Three-Dimensional Thermal Tomography Advances Cancer Treatment ...  

Because they grow more quickly than healthy cells, ... Solar Photovoltaic; ... the researchers discovered the effusivity values of damaged skin tissue differ from ...

407

Quantitative cerebral blood flow with optical coherence tomography  

E-Print Network (OSTI)

Absolute measurements of cerebral blood flow (CBF) are an important endpoint in studies of cerebral pathophysiology. Currently no accepted method exists for in vivo longitudinal monitoring of CBF with high resolution in ...

Srinivasan, Vivek J.

408

Body Wave Tomography For Regional Scale Assessment Of Geothermal...  

Open Energy Info (EERE)

Tibuleac Published: GRC, 2009 Document Number: Unavailable DOI: Unavailable Modeling-Computer Simulations At Central Nevada Seismic Zone Region (Biasi, Et Al., 2009)...

409

Multiple-energy Techniques in Industrial Computerized Tomography  

DOE R&D Accomplishments (OSTI)

Considerable effort is being applied to develop multiple-energy industrial CT techniques for materials characterization. Multiple-energy CT can provide reliable estimates of effective Z (Z{sub eff}), weight fraction, and rigorous calculations of absolute density, all at the spatial resolution of the scanner. Currently, a wide variety of techniques exist for CT scanners, but each has certain problems and limitations. Ultimately, the best multi-energy CT technique would combine the qualities of accuracy, reliability, and wide range of application, and would require the smallest number of additional measurements. We have developed techniques for calculating material properties of industrial objects that differ somewhat from currently used methods. In this paper, we present our methods for calculating Z{sub eff}, weight fraction, and density. We begin with the simplest case -- methods for multiple-energy CT using isotopic sources -- and proceed to multiple-energy work with x-ray machine sources. The methods discussed here are illustrated on CT scans of PBX-9502 high explosives, a lexan-aluminum phantom, and a cylinder of glass beads used in a preliminary study to determine if CT can resolve three phases: air, water, and a high-Z oil. In the CT project at LLNL, we have constructed several CT scanners of varying scanning geometries using {gamma}- and x-ray sources. In our research, we employed two of these scanners: pencil-beam CAT for CT data using isotopic sources and video-CAT equipped with an IRT micro-focal x-ray machine source.

Schneberk, D.; Martz, H.; Azevedo, S.

1990-08-01T23:59:59.000Z

410

Combining High-Energy X-Ray Tomography and Diffraction ...  

Science Conference Proceedings (OSTI)

Recent developments at the 1-ID beamline of the Advanced Photon Source will be ... Use of the APS was supported by the DOE/BES under Contract No.

411

Positron Emission Tomography (PET) at Brookhaven National Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

a long history of breakthrough developments in PET 2009: President Obama presents Dr. Fowler with the National Medal of Science Award for "exceptional accomplishments in the...

412

Optimal experiment design for time-lapse traveltime tomography  

SciTech Connect

Geophysical monitoring techniques offer the only noninvasive approach capable of assessing both the spatial and temporal dynamics of subsurface fluid processes. Increasingly, permanent sensor arrays in boreholes and on the ocean floor are being deployed to improve the repeatability and increase the temporal sampling of monitoring surveys. Because permanent arrays require a large up-front capital investment and are difficult (or impossible) to re-configure once installed, a premium is placed on selecting a geometry capable of imaging the desired target at minimum cost. We present a simple approach to optimizing downhole sensor configurations for monitoring experiments making use of differential seismic traveltimes. In our case, we use a design quality metric based on the accuracy of tomographic reconstructions for a suite of imaging targets. By not requiring an explicit singular value decomposition of the forward operator, evaluation of this objective function scales to problems with a large number of unknowns. We also restrict the design problem by recasting the array geometry into a low dimensional form more suitable for optimization at a reasonable computational cost. We test two search algorithms on the design problem: the Nelder-Mead downhill simplex method and the Multilevel Coordinate Search algorithm. The algorithm is tested for four crosswell acquisition scenarios relevant to continuous seismic monitoring, a two parameter array optimization, several scenarios involving four parameter length/offset optimizations, and a comparison of optimal multi-source designs. In the last case, we also examine trade-offs between source sparsity and the quality of tomographic reconstructions. One general observation is that asymmetric array lengths improve localized image quality in crosswell experiments with a small number of sources and a large number of receivers. Preliminary results also suggest that high-quality differential images can be generated using only a small number of optimally positioned sources.

Ajo-Franklin, J.B.

2009-10-01T23:59:59.000Z

413

Design Criteria and Eigensequence Plots for Satellite-Computed Tomography  

Science Conference Proceedings (OSTI)

The use of the “degrees of freedom for signal” is proposed as a design criteria for comparing different designs for satellite and other measuring systems. It is also proposed that certain eigensequence plots be examined at the design stage along ...

Grace Wahba

1985-06-01T23:59:59.000Z

414

High resolution seismic attenuation tomography at Medicine Lake Volcano, California  

DOE Green Energy (OSTI)

Medicine Lake Volcano, a broad shield volcano about 50km east of Mount Shasta in northern California, produced rhylotic eruptions as recently as 400 years ago. Because of this recent activity it is of considerable interest to producers of geothermal energy. In a joint project sponsored by the Geothermal Research Program of the USGS and the Division of Geothermal and Hydropower Division of the US-DOE, the USGS and LLNL conducted an active seismic experiment designed to explore the area beneath and around the caldera. The experiment of eight explosions detonated in a 50 km radius circle around the volcano recorded on a 11 x 15 km grid of 140 seismographs. The travel time data from the experiment have been inverted for structure and are presented elsewhere in this volume. In this paper we present the results of an inversion for 1/Q structure using t* data in a modified Aki inversion scheme. Although the data are noisy, we find that in general attenuative zones correlate with low velocity zones. In particular, we observe a high 1/Q zone roughly in the center of the caldera at 4 km depth in between two large recent dacite flows. This zone could represent the still molten or partially molten source of the flows.

Zucca, J.J.; Kasameyer, P.W.

1987-07-10T23:59:59.000Z

415

Multiple-energy techniques in industrial computerized tomography  

SciTech Connect

Considerable effort is being applied to develop multiple-energy industrial CT techniques for materials characterization. Multiple-energy CT can provide reliable estimates of effective Z (Z{sub eff}), weight fraction, and rigorous calculations of absolute density, all at the spatial resolution of the scanner. Currently, a wide variety of techniques exist for CT scanners, but each has certain problems and limitations. Ultimately, the best multi-energy CT technique would combine the qualities of accuracy, reliability, and wide range of application, and would require the smallest number of additional measurements. We have developed techniques for calculating material properties of industrial objects that differ somewhat from currently used methods. In this paper, we present our methods for calculating Z{sub eff}, weight fraction, and density. We begin with the simplest case -- methods for multiple-energy CT using isotopic sources -- and proceed to multiple-energy work with x-ray machine sources. The methods discussed here are illustrated on CT scans of PBX-9502 high explosives, a lexan-aluminum phantom, and a cylinder of glass beads used in a preliminary study to determine if CT can resolve three phases: air, water, and a high-Z oil. In the CT project at LLNL, we have constructed several CT scanners of varying scanning geometries using {gamma}- and x-ray sources. In our research, we employed two of these scanners: pencil-beam CAT for CT data using isotopic sources and video-CAT equipped with an IRT micro-focal x-ray machine source.

Schneberk, D.; Martz, H.; Azevedo, S.

1990-08-01T23:59:59.000Z

416

SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY: COMPENSATION FOR CONSTANT ATTENUATION  

E-Print Network (OSTI)

V. VI, VII. VII L INTRODUCTION THE MODIFIED PROJECTIONS THEATTENUATED BACK-PROJECTION OPERATOR THE FILTER FUNCTION AND= 0.25, 0.50, 1.00, 3.50 projection bin widths; attenuation

Gullberg, Grant T.

2013-01-01T23:59:59.000Z

417

Three-Dimensional Thermal Tomography Advances Cancer Treatment  

Jiangang Sun Contact Argonne Technology Development and Commercialization partners@anl.gov ne_TT3Dfs_0812. Title:

418

Electron Tomography in Aberration-corrected Transmission Electron ...  

Science Conference Proceedings (OSTI)

P1-04: 3D Microstructural Characterization of Uranium Oxide as a Surrogate Nuclear ... P1-15: Gating System Optimisation Design Study of a Cast Automobile ... P2-27: Characterization of Carbonate Rocks through X-ray Microtomography.

419

Development of a Time-Resolved Optical Tomography System for  

E-Print Network (OSTI)

that sequentially deliver near infrared (NIR) pulsed laser radiation of picosecond duration to the tissue. Transit of the internal absorption and scattering properties can be reconstructed from purely temporal data without suggested that a sufficient number of photons can be transmitted across the head of neonate at safe exposure

University College London

420

A Nonparametric Bayesian Approach For Emission Tomography Reconstruction  

SciTech Connect

We introduce a PET reconstruction algorithm following a nonparametric Bayesian (NPB) approach. In contrast with Expectation Maximization (EM), the proposed technique does not rely on any space discretization. Namely, the activity distribution--normalized emission intensity of the spatial poisson process--is considered as a spatial probability density and observations are the projections of random emissions whose distribution has to be estimated. This approach is nonparametric in the sense that the quantity of interest belongs to the set of probability measures on R{sup k} (for reconstruction in k-dimensions) and it is Bayesian in the sense that we define a prior directly on this spatial measure. In this context, we propose to model the nonparametric probability density as an infinite mixture of multivariate normal distributions. As a prior for this mixture we consider a Dirichlet Process Mixture (DPM) with a Normal-Inverse Wishart (NIW) model as base distribution of the Dirichlet Process. As in EM-family reconstruction, we use a data augmentation scheme where the set of hidden variables are the emission locations for each observed line of response in the continuous object space. Thanks to the data augmentation, we propose a Markov Chain Monte Carlo (MCMC) algorithm (Gibbs sampler) which is able to generate draws from the posterior distribution of the spatial intensity. A difference with EM is that one step of the Gibbs sampler corresponds to the generation of emission locations while only the expected number of emissions per pixel/voxel is used in EM. Another key difference is that the estimated spatial intensity is a continuous function such that there is no need to compute a projection matrix. Finally, draws from the intensity posterior distribution allow the estimation of posterior functionnals like the variance or confidence intervals. Results are presented for simulated data based on a 2D brain phantom and compared to Bayesian MAP-EM.

Barat, Eric; Dautremer, Thomas [CEA Saclay, Electronics and Signal Processing Laboratory, 91191 Gif sur Yvette (France)

2007-11-13T23:59:59.000Z

Note: This page contains sample records for the topic "tomography muon tomography" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

HEAVY-ION RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY  

E-Print Network (OSTI)

In: Biological and Medical Research with Accelerated Heavyeds. Biological and Medical Research with Accelerated HeavyIn: Biological and Medical Research with Accelerated Heavy

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

422

Applications of High Resolution X-ray Computed Tomography in ...  

Science Conference Proceedings (OSTI)

... data, including concentration profiles from x-ray absorption measurements during ... Dynamic Evolution of Liquid-liquid Phase Separation While Cooling in a

423

Calibration of High-Resolution X-Ray Tomography With ...  

Science Conference Proceedings (OSTI)

... The x-ray attenuation of the sample at this energy was close to the ... J. Coal Geol. ... G. Xu, DE Eastman, I. McNulty, SP Frigo, Y. Wang, CC Retsch, IC ...

2001-04-11T23:59:59.000Z

424

The Milky Way Tomography with SDSS: II. Stellar Metallicity  

E-Print Network (OSTI)

Using effective temperature and metallicity derived from SDSS spectra for ~60,000 F and G type main sequence stars (0.2

Zeljko Ivezic; Branimir Sesar; Mario Juric; Nicholas Bond; Julianne Dalcanton; Constance M. Rockosi; Brian Yanny; Heidi J. Newberg; Timothy C. Beers; Carlos Allende Prieto; Ron Wilhelm; Young Sun Lee; Thirupathi Sivarani; John E. Norris; Coryn A. L. Bailer-Jones; Paola Re Fiorentin; David Schlegel; Alan Uomoto; Robert H. Lupton; Gillian R. Knapp; James E. Gunn; Kevin R. Covey; J. Allyn Smith; Gajus Miknaitis; Mamoru Doi; Masayuki Tanaka; Masataka Fukugita; Steve Kent; Douglas Finkbeiner; Jeffrey A. Munn; Jeffrey R. Pier; Tom Quinn; Suzanne Hawley; Scott Anderson; Furea Kiuchi; Alex Chen; James Bushong; Harkirat Sohi; Daryl Haggard; Amy Kimball; John Barentine; Howard Brewington; Mike Harvanek; Scott Kleinman; Jurek Krzesinski; Dan Long; Atsuko Nitta; Stephanie Snedden; Brian Lee; Hugh Harris; Jonathan Brinkmann; Donald P. Schneider; Donald G. York

2008-04-24T23:59:59.000Z

425

The Milky Way Tomography with SDSS: II. Stellar Metallicity  

E-Print Network (OSTI)

Using effective temperature and metallicity derived from SDSS spectra for ~60,000 F and G type main sequence stars (0.2

Ivezic, Zeljko; Juric, Mario; Bond, Nicholas; Dalcanton, Julianne; Rockosi, Constance M; Yanny, Brian; Newberg, Heidi J; Beers, Timothy C; Prieto, Carlos Allende; Wilhelm, Ron; Lee, Young Sun; Sivarani, Thirupathi; Norris, John E; Bailer-Jones, Coryn A L; Fiorentin, Paola Re; Schlegel, David; Uomoto, Alan; Lupton, Robert H; Knapp, Gillian R; Gunn, James E; Covey, Kevin R; Smith, J Allyn; Miknaitis, Gajus; Doi, Mamoru; Tanaka, Masayuki; Fukugita, Masataka; Kent, Steve; Finkbeiner, Douglas; Munn, Jeffrey A; Pier, Jeffrey R; Quinn, Tom; Hawley, Suzanne; Anderson, Scott; Kiuchi, Furea; Chen, Alex; Bushong, James; Sohi, Harkirat; Haggard, Daryl; Kimball, Amy; Barentine, John; Brewington, Howard; Harvanek, Mike; Kleinman, Scott; Krzesinski, Jurek; Long, Dan; Nitta, Atsuko; Snedden, Stephanie; Lee, Brian; Harris, Hugh; Brinkmann, Jonathan; Schneider, Donald P; York, Donald G

2008-01-01T23:59:59.000Z

426

EMISSION AND TRANSMISSION NOISE PROPAGATION IN POSITRON EMISSION COMPUTED TOMOGRAPHY  

E-Print Network (OSTI)

26-29, 1979 EMISSION AND TRANSMISSION NOISE PROPAGATION INLBL-9783 EMISSION AND TRANSMISSION NOISE PROPAGATION INl·. LBL-9783 EMISSION AND TRANSMISSION NOISE PROPAGATION IN

Gullberg, G.T.

2010-01-01T23:59:59.000Z

427

Nitride semiconductors studied by atom probe tomography and correlative techniques  

E-Print Network (OSTI)

in hope or fear; But, grateful, take the good I find, The best of now and here.’ -- John Greenleaf Whittier Acknowledgements iv I am grateful to the many people who have helped and supported me during my three years in the Cambridge Centre... .2.1.2. Challenges to the island coalescence theory .................................................. 48 3.2.2. Effect of TDs ...................................................................................... 53 3.2.2.1. Non-radiative recombination model...

Bennett, Samantha

2011-02-08T23:59:59.000Z

428

Quantum state tomography of a fiber-based source of ...  

Science Conference Proceedings (OSTI)

... 2. RP Feynman, RB Leighton, RB and ML Sands, The Feynman Lectures ... fiber because the centro- symmetry of single-mode fiber glass allows no ...

2010-08-19T23:59:59.000Z

429

Nuclear resonance tomography with a toroid cavity detector  

DOE Patents (OSTI)

A toroid cavity detection system is described for determining the spectral properties and distance from a fixed point for a sample using Nuclear Magnetic Resonance. The detection system consists of a toroid with a central conductor oriented along the main axis of the toroidal cylinder and perpendicular to a static uniform magnetic field oriented along the main axis of the toroid. An rf signal is input to the central conductor to produce a magnetic field perpendicular to the central axis of the toroid and whose field strength varies as the inverse of the radius of the toroid. The toroid cavity detection system can be used to encapsulate a sample, or the detection system can be perforated to allow a sample to flow into the detection device or to place the samples in specified sample tubes. The central conductor can also be coated to determine the spectral property of the coating and the coating thickness. The sample is then subjected to the respective magnetic fields and the responses measured to determine the desired properties. 4 figs.

Woelk, K.; Rathke, J.W.; Klingler, R.J.

1996-11-12T23:59:59.000Z

430

Algorithmen f ur die 3D --Computer --Tomographie  

E-Print Network (OSTI)

Deutsch-russischen Institut für Energiepolitik und Energiewirtschaft e.V. durchgeführt wird. § 2 Beirat (1 Energiewirtschaft oder der energiewirtschaftlichen Forschung in den Beirat aufgenommen werden. Die Mitglieder des Unternehmen der Energiewirtschaft relevant sind. (5) Der Studiengang International Energy Economics

Louis, Alfred K.

431

RF, Thermal and Structural Analysis of the 201.25 MHz Muon Ionization Cooling Cavity  

E-Print Network (OSTI)

THERMAL AND STRUCTURAL ANALYSIS OF THE 201.25 MHZ MUON IONIZATION COOLINGthe thermal performance of the cavity, including the coolingthermal and structural behavior of the prototype 201.25 MHz cavity for a muon ionization cooling

Virostek, S.; Li, D.